Dual Affinity Polypeptides for Purification

Abstract

The present invention relates to a process for purification of a target biomolecule, comprising the steps: (a) contacting (i) a target biomolecule, (ii) a dual affinity polypeptide, and (iii) a solid support comprising a catching ligand, wherein the ratio between the equilibrium dissociation constants of the dual affinity polypeptide, [K_D,t/K_D,s], is at least 10° at standard conditions; and (b) recovering the target biomolecule by elution.

Description

REFERENCE TO SEQUENCE LISTING

[0001] This application contains a Sequence Listing in computer readable form. The computer readable form is incorporated herein by reference.

FIELD OF THE INVENTION

[0002] The present invention relates to a process for purification of a target biomolecule on a solid support comprising the steps: (a) contacting (i) a target biomolecule, (ii) a dual affinity polypeptide, and (iii) a solid support comprising a catching ligand.

BACKGROUND OF THE INVENTION

[0003] Recovery and purification of therapeutic proteins accounts for approximately 50% of the manufacturing cost of biological drugs. The general industrial purification process often includes a number of unit operation steps, like extraction, precipitation, as well as anion- and cation-exchange chromatography. Affinity chromatography is the preferred downstream process step due to its high recovery, yield and specificity, but the current cost and limitations of affinity chromatography is very substantial and in many cases prohibitive for a more general use of this unit operation. For a general description of conventional purification procedures including affinity chromatography see e.g. Jason and Ryden 1998 (Jason, J-C and Ryden, L., Protein Purification: Principles, high-Resolution, Methods and Applications, 2nd edition, Wiley & sons Inc. New York, 1998).

[0004] Conventional affinity chromatography is in general characterized by having a capturing ligand immobilised to a solid phase matrix. The ligand reversibly binds a target molecule present in a fluid such as liquid culture medium or serum. Target molecules are recovered by dissociating the complex at eluting conditions. Commercially available affinity matrices are in a ready to use format including capturing ligands covalently attached to the matrices. In conventional affinity chromatography the dissociation constant, K_D, between the ligand and the target protein is in the range of about 10^-5-10^-7M. Interactions with dissociation constants exceeding 10^-10-10^-11M are often impossible to use, as the conditions required to dissociate the complex are then the same as those that will result in denaturation of the target proteins.

[0005] The prior art include alternative variations of affinity chromatography purification methods described in the literature (Wilchek, M. and Gorecki, M. (1973), A New Approach for isolation of Biologically Active Compounds by Affinity Chromatography: Isolation of Trypsin).

[0006] FEBS Letters. 31, 1, 149-152, describes antibodies immobilized on an insoluble material. The antibodies have affinity for a certain ligand attached to a complex of two or more proteins, and are independent of the chemical, physical and biological properties of the complex itself. The immobilized antibody matrix serves as means for concentrating the complex. The adsorbed complex can then be recovered from the column by elution. The authors use the trypsin enzyme reacted with dinitrophenylated soybean trypsin inhibitor (DNP-STI) to form the complex. The complex is adsorbed to anti DNP-column and eluted under conditions that dissociate the antigen-antibody binding. The affinity column is then ready for the next purification cycle. The target trypsin is obtained by separation of the trypsin enzyme-dinitrophenylated soybean trypsin inhibitor complex into its components in a later step.

[0007] This procedure is different from the present invention in that the affinity column is reusable and it is the binding between the immobilized agent and the linker that is dissociated during elution and not the bond between linker and target biomolecule.

[0008] Another concept described by Hammarbergh, B. et al., (Proc. Natl. Acad. Sci USA, 86, 4367-4371 (1989)), is a fusion protein affinity approach and its use to express recombinant human insulin-like growth factor II. The procedure relates to a recombinant target protein of interest (X) fused between two different affinity protein tails (A and B). The protein (X) has a protease-sensitive site. A cell lysate containing the recombinant tripartite fusion protein is first passed through an affinity column containing a tail B-specific ligand. A mixture of full-length protein and proteolytic fragments containing the C-terminal fusion protein region can thus be obtained. In a second passage through a tail A-specific affinity column, the degraded proteins flow through while full-length fusion protein is retained. After site-specific cleavage of the tails, the protein of interest (X) is obtained by passing the cleavage mixture through a mixed affinity column for tails A and B and collecting the flow-through. The authors describe a procedure to obtain the target protein by expressing the target protein as an integrated part in between a dual affinity protein construct.

[0009] This is different from the present invention as the described affinity procedure requires two different affinity columns and that the immobilized ligand on the column and the dual affinity fusion protein is dissociated to recover the target biomolecule. Following the elution step and a regeneration procedure, the affinity columns are ready for the next affinity purification cycle. The target protein is only part of the fusion protein and is obtained following enzymatic degrading steps.

[0010] In a review article by, Ford, C. F., Suominen, I, Glatz, C. E. (1991) Fusion Tails for the Recovery and Purification of Recombinant Proteins. Protein Expression and Purification, 2, 95-107, the authors discuss the applications and advantages of using fusion tail systems to promote efficient recovery and purification of recombinant proteins from crude cell extracts or culture media. In these systems, a target protein is genetically engineered to contain a C- or N-terminal polypeptide tail, which provides the biochemical basis for specificity in recovery and purification. Fusion tails are useful for enhancing recovery methods for industrial downstream processing. Nevertheless, for the purification of target proteins a site for specific enzymatic cleavage is included, allowing removal of the tail after recovery. The article describes the application of fusion proteins with one binding partner having affinity for the ligand immobilized on a matrix. The procedures include an enzymatic cleavage step to recover the target protein from the fusion tail as required.

[0011] This is different from the present invention as the described affinity procedure requires that the fusion protein is dissociated from the ligand immobilized on the column matrix to recover the protein. Following the elution step and a regeneration procedure, the affinity column is ready for the next affinity purification cycle. Also, different from the present invention is that the target protein is part of the fusion protein and is only obtained following an enzymatic processing step.

[0012] In Rigaut, G. et al. (1991) (A Generic Protein Purification Method for Protein Complex Characterization and Proteom Exploration. Nature Biotechnology, 17, 1030-1032), is described a generic procedure for purification of protein complexes using tandem affinity purification (TAP) tag. The purification requires one affinity step followed by an enzymatic step cleaving the first affinity tag from the complex and a second affinity purification step to recover the target protein complex from the protease. Overall, the method involves two binding partners in combination both for binding to a ligand immobilized to a column matrix and a protease cleavage step to expose the second binding partner.

[0013] This is different from the present invention as the described affinity procedure requires that the fusion protein is dissociated from the ligand immobilized on the column matrix to recover protein. Following the elution step and a regeneration procedure, the affinity column is ready for the next affinity purification cycle. Also, different from the present invention is that the target protein is part of the fusion protein and is obtained following an enzymatic processing step.

[0014] EP1529844 describes a method for altering the properties of a recombinant target protein involving co-expression of target protein and the binding partner. The target protein and the binding partner form a complex in the cell. The complex formation result in altered properties such as accumulation, stability and/or integrity, sub-cellular localization, post-translational modifications, purification, and phase partitioning behavior of natural or recombinant target proteins expressed in a host organism. The binding partner may provide an affinity tag that enables co-purification of the complex and the target protein contained therein. This description is different from the present invention as it describes a co-expression of the binder and the target in order to form a complex in the cell. The disclosed method is for alteration of the target protein properties in general, whereas the present invention describes a dual affinity polypeptide specifically designed to facilitate a dedicated purification process, wherein the dual affinity polypeptides needs to possess specific binding properties.

[0015] Linder et al., (Linder, M., Nevanen, T., Soderholm, L., Bengs, O. and Teen, T., 1998, Biotechnology and Bioengineering, 60(5): 642-647) describes the use of CBD in fusionproteins for use as an affinity tag for purification. Some leakage from the column was observed.

[0016] Shpigel, E. et al. (Biotechnol. Appl. Biochem. (2000) 31, 197-203, "Expression, purification and application of Staphylococcal Protein A fused to cellulose-binding domain"), describes an example of purifying IgG using Protein A-CBD dual affinity polypeptide.

[0017] They claim that they save expensive coupling procedures by choosing immobilization of the Protein A functionality to a solid phase through the cellulose-binding domain (CBD) of a fusion protein. The fusion protein is immobilized on the column before adding the target.

[0018] Due to leakage problems this choice of dual affinity molecule is unsuitable for biopharmaceutical applications.

[0019] Sano et al. (U.S. Pat. No. 5,328,985) describes a fusion protein consisting of streptavidin and one or two immunoglobulin G (IgG) binding domains of protein A expressed in Escherichia coli. The strepavidin-protein A (ST-PA) fusion protein has functional biotin and IgG binding sites. Sano further describes complexes of the streptavidin-protein A fusion protein, a monoclonal antibody to bovine serum albumin (BSA) and biotinylated horseradish peroxidise. Sano also describes a method of labelling cell using the ST-PA fusion protein. Cells are incubated with an antibody to the cell surface antigen, Thy-1. The chimeric protein biotinylated marker complex is subsequently added to the cell suspension. This technique was used to deliver biotinylated FITC to the surface of the cells having Thy-1 antigens on their surface.

[0020] However, Sano does not describe or suggest using the ST-PA fusion protein as a tool for purification purposes nor does he describe a procedure of single use affinity chromatography column materials, nor recovery of a target protein.

[0021] WO 97/19957 describes an invention related to delivering toxins or nucleic acids into specific cell types using ST-PA fusion proteins for the purpose. Similar to Sano et al. (vide supra), an antibody recognise a surface antigen on the cell surface. The ST-PA binds to the antibody and facilitates a linkage to a biotinylated toxin bound to the biotin-binding site. However, it is not described or suggested to use the ST-PA fusion protein as a tool for purification purposes.

[0022] WO 01/95857 discloses a method and components for extracting toxic substances from mammalian blood. The method includes preparing an affinity column (extracorporeal device) and a procedure for extracorporeal extraction of toxic material from mammalian body fluids in connection with diagnosis or treatment of a mammalian condition or disease. The extracorporeal affinity column exemplified in the patent is made by coupling biotinylated entities to a matrix containing immobilized avidin. The biotinylated entity includes a part that binds strongly to the toxin in the mammalian blood. The toxic material is removed (i.e. immobilized but not recovered by elution from the column) from the blood following a conventional affinity chromatography procedure. The product from the flow through chromatography procedure is purified blood as the target (toxic materials) stays immobilized on the column after the process.

[0023] This is different from the present invention as it describes a procedure that bind the target tightly with high affinity in order to remove target from the product. The purification procedure is also different from the present invention as the product does not bind to the affinity column, but flows through and is collected as depleted from the toxic material (the target). The toxic material is not released or recovered.

[0024] WO 97/09068 discloses a method and chemical components that alter the equilibrium dissociation constant between two pairs of bio-molecules. The chemical component is a polymer that can be stimulated to change conformation and thus binding efficiency. The polymer is coupled e.g. to a specific site of the binding partner (the ligand) immobilised to the matrix of the affinity chromatography column. WO 97/09068 does not describe or suggest the use of a dual affinity component for affinity purification, nor recovering of target molecules.

[0025] In general, methods that will improve the capturing efficiency and simplify the purification process as well as reduce costs are desirable.

SUMMARY OF THE INVENTION

[0026] The present invention significantly improves and simplifies the downstream processing and lowers the cost of affinity chromatography processes in general. The present invention includes a generic capturing ligand immobilised to a matrix, a target biomolecule and a semi generic dual affinity polypeptide with different binding affinity toward the target and the capturing ligand respectively. The dual affinity polypeptide reacts with the target biomolecule to form a complex of medium binding affinity, and the complex binds non-covalently to a generic affinity matrix with a strong binding affinity. The target biomolecule is recovered by specific elution from the generic matrix leaving the dual affinity polypeptide attached to the capturing ligand on the matrix, due to the tight binding to the ligand preventing leakage from the solid phase matrix.

[0027] In a first aspect the present invention provides a process for purification of a target biomolecule, comprising the steps: (a) contacting (i) a target biomolecule, (ii) a dual affinity polypeptide, and (iii) a solid support comprising a catching ligand or dual affinity polypeptide binding site, wherein the ratio between the equilibrium dissociation constants of the dual affinity polypeptide, [K_D,t/K_D,s], is at least 10⁰ at standard conditions; and (b) recovering the target biomolecule by elution.

[0028] In a second aspect the present invention provides a process for purification of a target biomolecule, comprising the steps: (a) contacting (i) a target polypeptide, (ii) a dual affinity polypeptide, and (iii) a solid support comprising a catching ligand, wherein the dual affinity polypeptide has an equilibrium dissociation constant, K_D,t towards the target biomolecule in the range from 10^-2 to 10^-13 M, more particularly from 10^-4 to 10^-13 M at standard conditions, and wherein binding of the dual affinity polypeptide to the catching ligand on the solid support is provided by cleavage of a para-substituted benzyl guanine resulting in a thioether bond; and (b) recovering the target biomolecule by elution.

DETAILED DESCRIPTION OF THE INVENTION

[0029] In conventional affinity chromatography the capturing ligand is attached directly to the support. The main technical challenges are to optimize the entire system with regard to e.g. ligand coupling, nature of the support material, flow, backpressure and physical dimensions of the column. It should be understood that several of the technical limitations in high performance affinity columns are closely linked, making performance and cost optimization as well as scale up difficult. The ligand, in traditional affinity chromatography, preferably posses the following characteristics: [0030] a) The ligand should have chemical properties that allow easy covalent attachment to the matrix. [0031] b) The ligand must be able to form a reversible complex with the target molecule. [0032] c) The specificity of the ligand's affinity for the target molecule must be appropriate for the planned application. [0033] d) The dissociation constant for the ligand-target molecule complex under "loading conditions" should be strong enough to enable formation of stable complexes or to give sufficient retardation in the elution of the target molecule. [0034] e) It should be easy to dissociate the ligand from the target molecule by changing the conditions, e.g. pH or salt concentration, without irreversibly damaging either.

[0035] Furthermore, in traditional affinity chromatography, the ligand is normally covalently attached to the matrix and is also the component binding to the target molecule.

[0036] The capacity and quality of purification is greatly influenced by the contact time between target and ligand in the affinity column, the so-called residence time.

[0037] In addition to the association rate of the target protein to an immobilized ligand, diffusion into the pores within the chromatography beads in the column and mass transfer of the protein from the solute will impact the dynamic binding capacity of a chromatography matrix.

[0038] The mass transfer of the target protein from the solute depends on a variety of factors, including type and degree of cross-linking, compressibility of the support material, the size of the pores and the physical size of the target protein.

[0039] Flow rates, protein concentrations, column length, temperature, buffer, conductivity, and pH can also influence on pore diffusion and the dynamic binding capacity of the adsorbent.

[0040] Due to the requirement for rapid development of downstream processes and regulatory constraints, the residence time for a particular type of biological product such as for example a therapeutic antibody is typically fixed in the early development. Therefore, often the flow rate in the large scale column with e.g. larger bed height is tried adjusted to maintain the desired residence time used during the small scale development.

[0041] Due to technical constraints and the major investment required to purchase process-scale chromatography equipment, the scale up of traditional high performance affinity chromatography is a major challenge.

[0042] The present invention suggests a more simple and flexible scale up process with less technical constraints.

[0043] Furthermore, conventional affinity chromatography is characterised by regeneration procedures to provide repeated uses of the column materials. These cleaning procedures require extensive validation to allow multiple uses of the column.

[0044] The present invention differs in several aspects from the conventional affinity chromatography e.g. [0045] the immobilized ligand binds tightly to the dual affinity polypeptide (DAP) in order to prevent dissociation at elution conditions [0046] it is intended for single use applications

[0047] It is clear from the above that the role of the ligand in the present invention is to bind the DAP molecule and not the target molecule.

[0048] The attractive benefit of affinity chromatography is that it provides a large increase in purity with a minimal loss of target molecule material in a single unit operation. However, affinity chromatography is also characterised by the high cost prohibiting the use of large columns and thus favouring repetitive use of smaller columns. This leads to extended production processes and capacity loss proportional to the number of column reuses, increased loss and/or modification of the target molecule. In principle a typical affinity chromatography matrix can be used for up to 100 or more runs, but the average number of runs in manufacturing scale appears to be several fold lower. One of the reasons that the matrix is discarded long before the end of its theoretical lifespan is that the affinity columns used in manufacturing are dimensioned to process the entire fermentation batch in far less than 100 runs--in order to save cost, but also reduce the risk of contamination and handling failures. Rather than using the same matrix for several fermentation batches, the matrix may be discarded after processing of one fermentation batch, which leads to the relatively low number of average runs on an affinity matrix.

[0049] Controlling the flow rate through an affinity chromatography support is important in achieving binding. Flow rate through the column support is inextricably related to the efficiency of the separation; too fast a flow will cause the mobile phase to move past the beads faster than the diffusion time necessary to reach the internal bead volume. For each application a flow rate can be selected to achieve an optimal balance between efficient binding and elution of the target protein and a fast separation. Gravity driven flow chromatography is very slow and resolution of the protein separation can be adversely affected by secondary diffusion effects. Therefore modern systems have active pumping to control flow rates and continuous monitoring of back pressure to ensure that the maximum operating back pressure is not being exceeded.

[0050] In conventional columns fouling is of major concern. Debris, proteins and salts can slowly build up fouling layers in the channels of high performance affinity chromatography supports resulting in changed flow rates, reduced mass transfer rates, increased back pressure and hidden and deactivated affinity ligands. Especially lipids and lipoproteins material can rapidly clog chromatography columns and it is often necessary to remove them before affinity purification. This is especially important for samples derived from ascites fluid.

[0051] This pre purification step can be done by precipitation steps with for example dextran sulphate and polyvinylpyrrolidine followed by centrifugation and dialysis or desalting. The step can result in the loss of 5-10% of the target protein.

[0052] Omitting the delipidation step may be possible for the affinity purification system of the present invention as the column is single use. This will result in a higher overall target recovery and a more efficient downstream processing workflow.

[0053] Because of the intended single use of the columns according to the invention the elution step is also simplified. As the support material of the invention is not to be reused, one can more freely select elution conditions. For example, it is possible to select any elution buffers with an unconventional high concentration of salt, strong chaotropes, organic solvents etc. which will allow the recovery of the intact target and leave the DAP molecule attached to the support. It is of no importance if the properties of the support material are irreversibly changed with respect to e.g. structure and flow characteristics and cannot be reused.

[0054] This flexibility in selecting elution conditions is often not possible when using traditional high-performance affinity purification systems as the internal structures and surfaces are highly optimized and sensitive to polymer swelling or precipitation. Additionally, due to the cost of traditional affinity columns, the operators can be reluctant to test new elution conditions further reducing the flexibility in elution optimization.

[0055] The traditional operation of affinity purification includes cycles of equilibration, sample loading, elution and cleaning-in-place (CIP).

[0056] The cleaning steps or sanitization protocols have to be designed for each specific target purification. As described above, a major concern during operation is the build up of fouling layers or cross contamination between runs.

[0057] The cleaning step often includes using chemically harsh buffers like 0.1 M NaOH/1 M NaCl or 0.1 M phosphoric acid in a combination with sodium chloride or ethanol, followed by regeneration. It is well established that in general the dynamic binding capacity decreases as the number of CIP cycles increases. Therefore, one needs to find an optimum between the quality of the purified target, the number of runs, CIP's and the size and cost of the particular column. Further, the change of purification quality needs to be monitored for most pharmaceutical purifications.

[0058] As suggested by the present invention, the cost of this quality validation and the optimization of the CIP and runs can be greatly reduced.

[0059] In the conventional affinity chromatography outlined above for purification of e.g. monoclonal antibodies, the capturing ligand (Protein A) is attached to a solid phase matrix and has the affinity towards the target biomolecule (monoclonal antibodies). The present invention provides advantages compared to conventional affinity purification technologies for the downstream processing industry due to lower costs, high specificity and ease of use without compromising the quality of the down stream process. An essential feature of the present invention is the use of a dual affinity polypeptide as a linker between the target molecule and the solid support comprising a ligand. These dual affinity polypeptides are particularly useful for the downstream processing of biopharmaceutical and diagnostic proteins and peptides.

[0060] The invention suggests the improvement of the entire method of affinity purification by eliminating several of the constraints in current systems.

[0061] By using the dual affinity polypeptide (DAP) and the generic supports of the invention, the majority of the above problems and limitations can be completely eliminated or reduced.

[0062] According to the present invention the dual affinity purification technology is characterized by a generic solid support, which in one embodiment is a solid phase matrix, plus ready-to-use specific dual affinity polypeptides serving as linker molecules. A dual affinity polypeptide reacts with the target biomolecule. The dual affinity polypeptide--target biomolecule complex subsequently connects non-covalently to a capturing ligand immobilized on a solid support by contacting the complex and the solid support. The target biomolecule is recovered by specific elution. The dual affinity polypeptide remains attached to the ligand on the solid support during elution.

[0063] In one aspect the present invention therefore relates to a process for purification of a target biomolecule, comprising the steps: (a) contacting (i) a target biomolecule, (ii) a dual affinity polypeptide, and (iii) a solid support comprising a catching ligand or dual affinity polypeptide binding site, wherein the ratio between the equilibrium dissociation constants of the dual affinity polypeptide, [K_D,t/K_D,s], is at least 10° at standard conditions; and (b) recovering the target biomolecule by elution.

[0064] The dual affinity polypeptide acts as the linking partner between the solid support and the target molecule. In one particular embodiment the affinity of the dual affinity polypeptide towards the immobilized ligand is stronger than the affinity towards the target molecule. Furthermore this difference in binding affinity, can be expressed as the ratio between the equilibrium dissociation constants. In one embodiment this ration is at least 1.

[0065] The dual affinity polypeptide according to the invention comprises at least two binding sites, of which one binding site has affinity for the ligand and another binding site has affinity for the target molecule. These binding sites are polypeptide based meaning that they comprise either complete proteins or fragments of proteins. Such fragments should at least comprise the part of the protein containing the binding site for the specific target. The dual affinity polypeptide could be a fusion polypeptide or could be two or more polypeptides chemically linked in any suitable way e.g. by a linker segment.

[0066] Therefore the present invention in further embodiments relates to a dual affinity polypeptide having an equilibrium dissociation constant towards a target biomolecule, K_D,t in the range from 10^-2 to 10^-13 M, e.g. 10^-8 M, and an equilibrium dissociation constant towards a catching ligand, K_D,s in the range from 10^-6 to 10^-16 M, e.g. 10^-10 M, and at the same time the ratio, K_D,t/K_D,s, should be matched such that the ratio is at least 10°, more particularly at least 10¹, more particularly 10², more particularly 10³ and even more particularly 10⁴

[0067] The above in other words means that binding of DAP to the target is in preferred embodiments weaker than binding of DAP to the ligand.

[0068] Particularly the said dual affinity polypeptide has an equilibrium dissociation constant, K_D,t towards the target polypeptide in the range from 10^-4 to 10^-13 M, more particularly in the range from 10^-6 to 10^-13 M, and an equilibrium dissociation constant, K_D,s towards the catching ligand in the range from 10^-6 to 10^-16 M, more particularly in the range from 10^-11 to 10^-16 M.

[0069] In general the binding towards the ligand or the column cannot be too strong. Therefore the value at the upper end of the range is not important in respect of K_D,s.

[0070] In the context of the present invention the equilibrium dissociation constant are measured according to the reaction:

A + B ⇄ k d k a AB ##EQU00001##

[0071] A and B represents the binding partners: the target biomolecule and the dual affinity polypeptide or the dual affinity polypeptide and the catching ligand immobilized on the solid phase matrix.

[0072] The rate constants for the reaction above represent the rate at which the two molecules A and B associates and dissociates

Dissociation rate - [ AB ] t = k d [ AB ] ##EQU00002## Association rate : [ AB ] t = k a [ A ] [ B ] ##EQU00002.2##

[0073] When the rates are equal at equilibrium k_a[A][B]=k_d [AB], which gives

k d k a = [ A ] [ B ] [ AB ] = K D ##EQU00003## k a k d = [ AB ] [ A ] [ B ] = K A ##EQU00003.2##

[0074] The candidate binding domains to be employed in the dual affinity polypeptide should be evaluated according to the apparent equilibrium dissociation constants based on the total binding affinity of each of the dual affinities in a given DAP molecule irrespective of whether it contains one or several binding domains for each specificity (target/capturing ligand). If e.g. A and B represent protein A (has four to five binding domains) and avidin (having four binding sites) respectively the above ranges should apply for one protein A molecule fused to one avidin molecule. However, this does not exclude the possibility that e.g. the DAP molecule could be composed of several binding candidates for the target and several candidates for the ligand on the matrix. The DAP could e.g. in another embodiment consist of 3 protein A molecules linked to one or more avidin molecules. Therefore the specified ranges as defined above should in the context of the present invention be evaluated based on the apparent binding constants for the binding domains in common.

[0075] In the context of the present invention the specified equilibrium dissociation constants are determined by surface plasmon resonance (SPR) technology using a Biacore Instrument as illustrated in detail in the examples. The conditions described herein represent the standard conditions. As a suitable starting point for selecting different binding domains to be combined in the DAP molecule published K_D's may be used.

[0076] The two binding pairs should be selected based on the K_D's during specific binding conditions, but also considering the planned elution conditions, when the target is recovered and the DAP molecule remains on the support.

[0077] As described above determination of dissociation affinities of various binding domains in the context of a DAP molecule was accomplished by using surface plasmon resonance (SPR). Such evaluation can be done with the Biacore system. Biacore has commercial instrumentation where measurements based on SPR make determinations on protein-protein interactions. The evaluation was conducted having the complete DAP immobilized on the sensor chip used in the Biacore instrument. The Biacore system defines the characteristics of proteins in terms of their specificity of interaction with other molecules, the rates at which they interact (association and dissociation), and their affinity (how tightly they bind to another molecule). This technique has been described e.g. for determining the binding intereactions between specific antibodies and their target (see e.g. Ronnmark, 2002, Eur. J. Biochem., 269: 2647-2655).

[0078] In the examples below several DAP candidates have been evaluated and their binding affinities under standard conditions (as described in the examples) have been measured for the complete DAP. Other methods may also be used, however, results may then differ. A list of alternative methods has been described below.

[0079] Quantitative measurement of non-covalent protein-ligand interactions is well known. The methods suited for quantitative measurement of binding constants of particular relevance for the present invention include various versions of surface plasmon resonance (SPR) and circular dichroism (CD).

[0080] Other methods include mass spectrometry methods for dynamic titrations like ESI-MS titration, HPLC-ESI-MS titration or MALDI-SUPREX titration.

[0081] Other methods are based on determining the dissociation constant of a ligand at a binding site indirectly by competitive displacement of a radioactive ligand or by measurement of NMR chemical shift as function of concentration, fluorescence spectroscopy analysis of e.g. signal quenching, X-ray crystallographic measurement of the ligand occupancy, isothermal calorimetry (ITC) or enzyme inhibition.

[0082] Yet other methods use labeled ligands, for example capillary electrophoresis with laser-induced fluorescence detection of enzyme labeled ligands.

[0083] Alternatively, binding constants can be found from computational techniques by using de novo design, data mining and sophisticated algorithms.

[0084] In the context of the present invention the appropriate ranges for the equilibrium dissociation constants as specified in the claims should apply to the complete dual affinity polypeptide and not to the individual binding parts measured separately.

[0085] Moreover, if a single candidate binding domain has a weaker binding affinity towards the target or ligand than required according to the present invention, it still could be applicable by combining several such candidate binding domains into one DAP.

[0086] This is due to the valence effect. It is possible to obtain an increased binding strength due to an avidity gain. Single domains with a low intrinsic affinity combined into multimers often generates avidity effects which lead to slower dissociation rates and increased functional affinities by more than 100 fold (MacKenzie, C. R. et al (1996), Analysis by surface plasmon resonance of the influence of valence on the ligand binding affinities and kinetics of and anti carbohydrate antibody. Journal of Biological Chemistry, 271, 1527-1533). It is possible to measure effects from monovalent and bivalent bindings, but at higher binding valences the situation becomes so complex that it is impossible to distinguish between different binding valances. Nevertheless relative data can be obtained and are used in the context of the present invention

[0087] The invention provides a purification procedure wherein the first reaction between the target molecule and the dual affinity polypeptide in one particular embodiment can be completed in free solution. Reaction binding kinetics is about 1000 times faster in free solution compared to interface reactions (Nygren, H. and Stenberg, M. (1989) Immunochemistry at interfaces. Immunology, 66, 321-327).

[0088] The target molecule-dual affinity polypeptide complexes are subsequently presented to and bind efficiently to the ligand on the solid support. The strong binding (fast association rate and slow dissociation rate of the ligand towards the dual affinity polypeptide) depletes the mobile phase of target-DAP complexes. The target molecules are recovered from solution through this sequential procedure facilitated by the second binding functionality of the dual affinity polypeptide.

[0089] Due to the described differences in equilibrium dissociation constants the target polypeptide can be efficiently eluted without eluting the dual affinity polypeptide. Elution can in one embodiment be performed by changing either pH, ionic strength or chaotropic ions in solution, or any combination thereof.

[0090] The K_D value can be influenced by changing conditions like pH, ionic strength, temperature and polar properties. Unfortunately, the literature values for K_D are not always listed at relevant elution conditions. Though, the skilled in the art will be able to find elution conditions which will only break the weakest binding without disturbing the stronger binding in cases were the binding to the solid matrix is sufficiently strong (i.e. K_D,s<10^-9 M and the ratio between K_D values is at least 1 when measured at standard binding conditions).

[0091] The criteria for selecting the target specific binding pairs of the invention resemble those for the traditional affinity chromatography with regard to dissociation constant, specificity, binding and possible elution conditions. However, since elution conditions are usually different from the conditions applied when measuring K_D's on the Biacore instrument in the present invention the limits set for the applicable ranges of the two distinct binding affinities of the DAP has been determined under standard conditions, which equals the conditions used in the examples.

[0092] The criteria for selecting the specific ligand binding domains of the invention are somewhat different from the criteria used in the traditional affinity chromotography, as the DAP molecule is not to be eluted from the support.

[0093] Binding domains which are specific and strong, but cannot be broken under normal elution conditions are not suited for traditional affinity chromatography. Such binding domains can be used in the present invention. Examples include the very specific biotin-Streptavidin binding, which for most practical applications cannot be reversed under elution conditions and consequently is well suited as one of the binding pairs of the invention.

[0094] In general, the binding between DAP and the ligand should be stronger than the binding between DAP and the target and strong enough to prevent leakage of the DAP molecule from the support during elution of the target.

[0095] Preferred ligand-DAP binding pairs are strong and exhibit no or little reduction in binding strength due to changing pH, ionic strength, solvents, chaotropic agents, temperature etc.

[0096] It should be clear that when changing the scale of purification, using the system of the invention, the amount of DAP added is adjusted to the amount and concentration of target protein. As the DAP molecule can be supplied as a concentrate, the binding conditions can be adjusted with respect to e.g. pH and salts. Also, the temperature and time can be selected to give the best binding and subsequently purification.

[0097] The size and capacity of the generic column is selected to be large enough to capture the DAP molecules. Potentially several columns are used in parallel or in a bundle.

[0098] If purifying another target, another appropriate DAP molecule is selected. The same or another column can be used.

[0099] In one embodiment the dual affinity polypeptide is a fusion polypeptide. Such fusion polypeptides can either be prepared by chemically linking two appropriate proteins or alternatively in another embodiment the fusion protein can be synthesized as a recombinant polypeptide. The fusion polypeptide can be linked in any suitable way e.g. by a linker segment. and the fusion polypeptide should at least comprise the binding domains of the selected proteins. The linker peptide should be selected in such a way that it is not unstable resulting in degradation. The linker could e.g. be a highly O-glycosylated linker as linkers between catalytic domains and carbohydrate binding domains known from fungal carbohydrases, or it could be proline rich linkers.

[0100] The dual affinity polypeptide comprises at least one binding domain capable of binding to the target biomolecule with the desired binding specificity as described. The binding domain can be comprised in the complete protein or it can be a fragment of the protein which has retained its binding specificity. Many proteins have been described in the literature displaying affinity towards biomolecules, e.g. peptides, proteins, DNA, RNA, carbohydrates, and all such proteins or fragments thereof are potentially useful in the context of the present invention as candidates for the dual affinity polypeptide.

[0101] The said binding domain directed towards the target biomolecule can in one embodiment therefore be selected from but not limited to the group consisting of protein A, protein A fragments, protein A derived domains (e.g. domains known as an Affibody®), antibodies, antibody fragments, lipocalins, and lectins.

[0102] Combinatorial protein engineering has been applied to develop artificial proteins that can bind to selected targets with high affinity and be used as alternatives to antibodies (Nygren, P.-Å. & Skerra, A. (2004). Binding proteins from alternative scaffolds. J. Immunol. Methods, 290, p. 3-28; Binz, H. K. & Pluckthun, A. (2005). Engineered proteins as specific binding reagents. Curr. Opin. Biotech. 16, p. 459-469). In the context of the present invention the term "affibody" defines a class of engineered proteins selected for their specific binding activity towards a desired target and based on the Z domain, which is a 58 residue three-helical bundle derived by a single amino acid substitution in the B domain of staphylococcal protein A (SPA) (Nilsson, B., Moks, T., Jansson, B., Abrahmsen, L., Elmblad, A., Holmgren, E. et al. (1987) Protein Eng. 1, p. 107-113). The Z domain binds to the Fc region of immunoglobulins as do the five homologous SPA domains, but unlike the parental domain it does not bind to the Fab region. Such affibodies are examples of a protein A derived binding domain.

[0103] The dual affinity polypeptide also comprises at least one binding domain capable of binding to the catching ligand immobilized on the solid support. This second binding domain can be comprised in the complete protein or it can be a fragment of the protein which has retained its binding specificity. In one embodiment the second binding domain is selected from but not limited to the group consisting of avidin, streptavidin, neutravidin, steroid receptor, antibody, antibody fragment, amyloglucosidase (AMG), enzyme domain (e.g. cellulose binding domain, CBD), lipocalins, and lectins. As stated above these candidates, for the second binding domain, are meant as examples illustrating the invention, however, these examples should not be seen as the only usable combinations.

[0104] In one embodiment the antibody is selected from the group consisting of Llama and camel antibodies.

[0105] In a particular embodiment the dual affinity polypeptide according to the invention comprises at least one binding domain of protein A fused to at least one biotin binding domain of avidin, streptavidin or neutravidin.

[0106] In a particular embodiment the dual affinity polypeptide according to the invention comprises at least one binding domain of a protein A derived binding domain fused to at least one biotin binding domain of avidin, streptavidin or neutravidin.

[0107] In another particular embodiment the dual affinity polypeptide comprises at least one binding domain of an affibody fused to at least one biotin binding domain of avidin, streptavidin or neutravidin.

[0108] In another particular embodiment the dual affinity polypeptide comprises at least one binding domain of an antibody fused to at least one biotin binding domain of avidin, streptavidin or neutravidin.

[0109] In another particular embodiment the dual affinity polypeptide comprises at least one binding domain of protein A fused to AMG, CBD or (VhhRR6(R2)).

[0110] In another particular embodiment the dual affinity polypeptide comprises at least one binding domain of a protein A derived binding domain fused to AMG, CBD or (VhhRR6(R2)).

[0111] In another particular embodiment the dual affinity polypeptide comprises at least one binding domain of an affibody fused to AMG, CBD or (VhhRR6(R2)).

[0112] In another particular embodiment the dual affinity polypeptide comprises at least one binding domain of an antibody fused to AMG, CBD or (VhhRR6(R2)).

[0113] The dual affinity polypeptide can as illustrated in the examples be linked chemically; however, a more cost efficient way to produce the dual affinity polypeptide would be to express it as a recombinant fusion protein.

[0114] In one embodiment of the invention, the fusion polypeptide is produced as a recombinant polypeptide.

[0115] Another possibility also envisioned would be to co-express the fusion protein and the target biomolecule in the host cell making it possible to load the crude cell culture extract directly on the solid support.

[0116] In a further embodiment the target biomolecule and the DAP is expressed separately but in the same type of host cell.

[0117] In a particular embodiment the fusion protein is expressed as a recombinant protein, particularly the fusion protein is in one embodiment recombinant Streptavidin linked to protein A. Such fusion protein can be produced intracellular in E. coli as described in Sano (T. Sano and C. R. Cantor (1991) BioTechnology 9 p 1378-1381), preferentially using the construct pTSAPA-2 carrying two IgG binding domains. However this construct is not industrially feasible as intracellular production with recovery of inclusion bodies in E. coli do not give industrially relevant yields and the production process is highly complex. A process based on a secreted fusion produced in e.g. Bacillus or Aspergillus is of much higher industrial relevance.

[0118] The nucleotide sequence encoding the fusion protein according to the invention may preferably be expressed by inserting the nucleotide sequence or a nucleic acid construct comprising the sequence into an appropriate vector for expression. In creating the expression vector, the coding sequence is located in the vector so that the coding sequence is operably linked with the appropriate control sequences for expression.

[0119] The recombinant expression vector may be any vector (e.g., a plasmid or virus) which can be conveniently subjected to recombinant DNA procedures and can bring about expression of the nucleotide sequence. The choice of the vector will typically depend on the compatibility of the vector with the host cell into which the vector is to be introduced. The vectors may be linear or closed circular plasmids.

[0120] The vector may be an autonomously replicating vector, i.e., a vector which exists as an extrachromosomal entity, the replication of which is independent of chromosomal replication, e.g., a plasmid, an extrachromosomal element, a minichromosome, or an artificial chromosome. The vector may contain any means for assuring self-replication. Alternatively, the vector may be one which, when introduced into the host cell, is integrated into the genome and replicated together with the chromosome(s) into which it has been integrated. Furthermore, a single vector or plasmid or two or more vectors or plasmids which together contain the total DNA to be introduced into the genome of the host cell, or a transposon may be used.

[0121] The vectors of the present invention preferably contain one or more selectable markers which permit easy selection of transformed cells. A selectable marker is a gene the product of which provides for biocide or viral resistance, resistance to heavy metals, prototrophy to auxotrophs, and the like.

[0122] A conditionally essential gene may function as a non-antibiotic selectable marker. Non-limiting examples of bacterial conditionally essential non-antibiotic selectable markers are the dal genes from Bacillus subtilis, Bacillus licheniformis, or other Bacilli, that are only essential when the bacterium is cultivated in the absence of D-alanine. Also the genes encoding enzymes involved in the turnover of UDP-galactose can function as conditionally essential markers in a cell when the cell is grown in the presence of galactose or grown in a medium which gives rise to the presence of galactose. Non-limiting examples of such genes are those from B. subtilis or B. licheniformis encoding UTP-dependent phosphorylase (EC 2.7.7.10), UDP-glucose-dependent uridylyltransferase (EC 2.7.7.12), or UDP-galactose epimerase (EC 5.1.3.2). Also a xylose isomerase gene such as xyIA, of Bacilli can be used as selectable markers in cells grown in minimal medium with xylose as sole carbon source. The genes necessary for utilizing gluconate, gntK, and gntP can also be used as selectable markers in cells grown in minimal medium with gluconate as sole carbon source. Other examples of conditionally essential genes are known in the art. Antibiotic selectable markers confer antibiotic resistance to such antibiotics as ampicillin, kanamycin, chloramphenicol, erythromycin, tetracycline, neomycin, hygromycin or methotrexate.

[0123] Suitable markers for yeast host cells are ADE2, HIS3, LEU2, LYS2, MET3, TRP1, and URA3. Selectable markers for use in a filamentous fungal host cell include, but are not limited to, amdS (acetamidase), argB (ornithine carbamoyltransferase), bar (phosphinothricin acetyltransferase), hph (hygromycin phosphotransferase), niaD (nitrate reductase), pyrG (orotidine-5'-phosphate decarboxylase), sC (sulfate adenyltransferase), and trpC (anthranilate synthase), as well as equivalents thereof. Preferred for use in an Aspergillus cell are the amdS and pyrG genes of Aspergillus nidulans or Aspergillus oryzae and the bar gene of Streptomyces hygroscopicus.

[0124] The vectors of the present invention preferably contain an element(s) that permits integration of the vector into the host cell's genome or autonomous replication of the vector in the cell independent of the genome.

[0125] For integration into the host cell genome, the vector may rely on the polynucleotide's sequence encoding the polypeptide or any other element of the vector for integration into the genome by homologous or nonhomologous recombination. Alternatively, the vector may contain additional nucleotide sequences for directing integration by homologous recombination into the genome of the host cell at a precise location(s) in the chromosome(s). To increase the likelihood of integration at a precise location, the integrational elements should preferably contain a sufficient number of nucleic acids, such as 100 to 10,000 base pairs, preferably 400 to 10,000 base pairs, and most preferably 800 to 10,000 base pairs, which have a high degree of identity with the corresponding target sequence to enhance the probability of homologous recombination. The integrational elements may be any sequence that is homologous with the target sequence in the genome of the host cell. Furthermore, the integrational elements may be non-encoding or encoding nucleotide sequences. On the other hand, the vector may be integrated into the genome of the host cell by non-homologous recombination.

[0126] For autonomous replication, the vector may further comprise an origin of replication enabling the vector to replicate autonomously in the host cell in question. The origin of replication may be any plasmid replicator mediating autonomous replication which functions in a cell. The term "origin of replication" or "plasmid replicator" is defined herein as a nucleotide sequence that enables a plasmid or vector to replicate in vivo.

[0127] Examples of bacterial origins of replication are the origins of replication of plasmids pBR322, pUC19, pACYC177, and pACYC184 permitting replication in E. coli, and pUB110, pE194, pTA1060, and pAMβ1 permitting replication in Bacillus.

[0128] Examples of origins of replication for use in a yeast host cell are the 2 micron origin of replication, ARS1, ARS4, the combination of ARS1 and CEN3, and the combination of ARS4 and CEN6.

[0129] Examples of origins of replication useful in a filamentous fungal cell are AMA1 and ANS1 (Gems et al., 1991, Gene 98:61-67; Cullen et al., 1987, Nucleic Acids Research 15: 9163-9175; WO 00/24883). Isolation of the AMA1 gene and construction of plasmids or vectors comprising the gene can be accomplished according to the methods disclosed in WO 00/24883.

[0130] More than one copy of a polynucleotide of the present invention may be inserted into the host cell to increase production of the gene product. An increase in the copy number of the polynucleotide can be obtained by integrating at least one additional copy of the sequence into the host cell genome or by including an amplifiable selectable marker gene with the polynucleotide where cells containing amplified copies of the selectable marker gene, and thereby additional copies of the polynucleotide, can be selected for by cultivating the cells in the presence of the appropriate selectable agent.

[0131] The procedures used to ligate the elements described above to construct the recombinant expression vectors of the present invention are well known to one skilled in the art (see, e.g., Sambrook et al., 1989, supra).

[0132] The present invention also relates to recombinant host cells, comprising a polynucleotide of the present invention, which are advantageously used in the recombinant production of the polypeptides. A vector comprising a polynucleotide of the present invention is introduced into a host cell so that the vector is maintained as a chromosomal integrant or as a self-replicating extra-chromosomal vector as described earlier. The term "host cell" encompasses any progeny of a parent cell that is not identical to the parent cell due to mutations that occur during replication. The choice of a host cell will to a large extent depend upon the gene encoding the polypeptide and its source.

[0133] The host cell may be a unicellular microorganism, e.g., a prokaryote, or a non-unicellular microorganism, e.g., a eukaryote.

[0134] Useful unicellular microorganisms are bacterial cells such as gram positive bacteria including, but not limited to, a Bacillus cell, e.g., Bacillus alkalophilus, Bacillus amyloliquefaciens, Bacillus brevis, Bacillus circulans, Bacillus clausii, Bacillus coagulans, Bacillus lautus, Bacillus lentus, Bacillus licheniformis, Bacillus megaterium, Bacillus stearothermophilus, Bacillus subtilis, and Bacillus thuringiensis; or a Streptomyces cell, e.g., Streptomyces lividans and Streptomyces murinus, or gram negative bacteria such as E. coli and Pseudomonas sp.

[0135] In a preferred aspect, the bacterial host cell is a Bacillus lentus, Bacillus licheniformis, Bacillus stearothermophilus, or Bacillus subtilis cell. In another preferred aspect, the Bacillus cell is an alkalophilic Bacillus.

[0136] The introduction of a vector into a bacterial host cell may, for instance, be effected by protoplast transformation (see, e.g., Chang and Cohen, 1979, Molecular General Genetics 168: 111-115), using competent cells (see, e.g., Young and Spizizin, 1961, Journal of Bacteriology 81: 823-829, or Dubnau and Davidoff-Abelson, 1971, Journal of Molecular Biology 56: 209-221), electroporation (see, e.g., Shigekawa and Dower, 1988, Biotechniques 6: 742-751), or conjugation (see, e.g., Koehler and Thorne, 1987, Journal of Bacteriology 169: 5771-5278).

[0137] The host cell may also be a eukaryote, such as a mammalian, insect, plant, or fungal cell.

[0138] In a preferred aspect, the host cell is a fungal cell. "Fungi" as used herein includes the phyla Ascomycota, Basidiomycota, Chytridiomycota, and Zygomycota (as defined by Hawksworth et al., In, Ainsworth and Bisby's Dictionary of The Fungi, 8th edition, 1995, CAB International, University Press, Cambridge, UK) as well as the Oomycota (as cited in Hawksworth et al., 1995, supra, page 171) and all mitosporic fungi (Hawksworth et al., 1995, supra).

[0139] In a more preferred aspect, the fungal host cell is a yeast cell. "Yeast" as used herein includes ascosporogenous yeast (Endomycetales), basidiosporogenous yeast, and yeast belonging to the Fungi Imperfecti (Blastomycetes). Since the classification of yeast may change in the future, for the purposes of this invention, yeast shall be defined as described in Biology and Activities of Yeast (Skinner, F. A., Passmore, S. M., and Davenport, R. R., eds, Soc. App. Bacteriol. Symposium Series No. 9, 1980).

[0140] In an even more preferred aspect, the yeast host cell is a Candida, Hansenula, Kluyveromyces, Pichia, Saccharomyces, Schizosaccharomyces, or Yarrowia cell.

[0141] In a most preferred aspect, the yeast host cell is a Saccharomyces carlsbergensis, Saccharomyces cerevisiae, Saccharomyces diastaticus, Saccharomyces douglasii, Saccharomyces kluyveri, Saccharomyces norbensis or Saccharomyces oviformis cell. In another most preferred aspect, the yeast host cell is a Kluyveromyces lactis cell. In another most preferred aspect, the yeast host cell is a Yarrowia lipolytica cell.

[0142] In another more preferred aspect, the fungal host cell is a filamentous fungal cell. "Filamentous fungi" include all filamentous forms of the subdivision Eumycota and Oomycota (as defined by Hawksworth et al., 1995, supra). The filamentous fungi are generally characterized by a mycelial wall composed of chitin, cellulose, glucan, chitosan, mannan, and other complex polysaccharides. Vegetative growth is by hyphal elongation and carbon catabolism is obligately aerobic. In contrast, vegetative growth by yeasts such as Saccharomyces cerevisiae is by budding of a unicellular thallus and carbon catabolism may be fermentative.

[0143] In an even more preferred aspect, the filamentous fungal host cell is an Acremonium, Aspergillus, Aureobasidium, Bjerkandera, Ceriporiopsis, Coprinus, Coriolus, Cryptococcus, Filobasidium, Fusarium, Humicola, Magnaporthe, Mucor, Myceliophthora, Neocallimastix, Neurospora, Paecilomyces, Penicillium, Phanerochaete, Phlebia, Piromyces, Pleurotus, Schizophyllum, Talaromyces, Thermoascus, Thielavia, Tolypocladium, Trametes, or Trichoderma cell.

[0144] In a most preferred aspect, the filamentous fungal host cell is an Aspergillus awamori, Aspergillus fumigatus, Aspergillus foetidus, Aspergillus japonicus, Aspergillus nidulans, Aspergillus niger or Aspergillus oryzae cell. In another most preferred aspect, the filamentous fungal host cell is a Fusarium bactridioides, Fusarium cerealis, Fusarium crookwellense, Fusarium culmorum, Fusarium graminearum, Fusarium graminum, Fusarium heterosporum, Fusarium negundi, Fusarium oxysporum, Fusarium reticulatum, Fusarium roseum, Fusarium sambucinum, Fusarium sarcochroum, Fusarium sporotrichioides, Fusarium sulphureum, Fusarium torulosum, Fusarium trichothecioides, or Fusarium venenatum cell. In another most preferred aspect, the filamentous fungal host cell is a Bjerkandera adusta, Ceriporiopsis aneirina, Ceriporiopsis aneirina, Ceriporiopsis caregiea, Ceriporiopsis gilvescens, Ceriporiopsis pannocinta, Ceriporiopsis rivulosa, Ceriporiopsis subrufa, or Ceriporiopsis subvermispora, Coprinus cinereus, Coriolus hirsutus, Humicola insolens, Humicola lanuginosa, Mucor miehei, Myceliophthora thermophila, Neurospora crassa, Penicillium purpurogenum, Phanerochaete chrysosporium, Phlebia radiata, Pleurotus eryngii, Thielavia terrestris, Trametes villosa, Trametes versicolor, Trichoderma harzianum, Trichoderma koningii, Trichoderma longibrachiatum, Trichoderma reesei, or Trichoderma viride cell.

[0145] Fungal cells may be transformed by a process involving protoplast formation, trans-formation of the protoplasts, and regeneration of the cell wall in a manner known per se. Suitable procedures for transformation of Aspergillus and Trichoderma host cells are described in EP 238 023 and Yelton et al., 1984, Proceedings of the National Academy of Sciences USA 81: 1470-1474. Suitable methods for transforming Fusarium species are described by Malardier et al., 1989, Gene 78: 147-156, and WO 96/00787. Yeast may be transformed using the procedures described by Becker and Guarente, In Abelson, J. N. and Simon, M. I., editors, Guide to Yeast Genetics and Molecular Biology, Methods in Enzymology, Volume 194, pp 182-187, Academic Press, Inc., New York; Ito et al., 1983, Journal of Bacteriology 153: 163; and Hinnen et al., 1978, Proceedings of the National Academy of Sciences USA 75: 1920.

[0146] The contact between the target biomolecule, the dual affinity polypeptide (DAP), and the solid support can be performed in several optional ways. In one embodiment all components could be brought into contact in one step, eg. by loading the target polypeptide and the fusion protein on the solid support without pre-incubation in solution. The dual affinity polypeptide can however, be contacted with the target before loading this complex on the solid support. In this embodiment the target biomolecule and the dual affinity polypeptide are contacted first, e.g. in solution, and subsequently the formed complex is contacted with the solid support. Depending on the nature of the solid support preferred embodiments of this principle could differ.

[0147] In one preferred embodiment the solid support is a solid phase matrix. This includes conventional solid phase matrixes. In the case of solid phase matrixes in the form of columns, the target and the dual affinity polypeptide can in one embodiment be contacted first in solution and subsequently contacted with the solid phase matrix by loading the complex onto the column.

[0148] It can be envisioned however, that e.g. the dual affinity polypeptide can be loaded on the solid support first and subsequently loading the target biomolecule

[0149] In another embodiment the solid support is in the form of particles, in which case the order of contact is of less importance, and the contact of all the components could conveniently be performed in solution in one step or in several steps.

[0150] The catching ligand according to the invention is covalently attached to the solid support. As explained above the ligand according to the present invention is different from the ligand used in traditional affinity chromatography where the purpose of the ligand is to bind the target. In the present invention the ligand should bind to the DAP. Ligands are well known in the art and below are given examples that can be applied according to the invention. In the context of the present invention in one particular embodiment instead of a ligand attached to the solid phase the solid phase could alternatively comprise a binding affinity or binding site towards the DAP. An example could be cellulose as the solid phase and CBD (cellulose binding domain) as part of the DAP.

[0151] In one embodiment the ligand is chosen from but not limited to the group consisting of biotin, acarbose, steroids, haptens, epitope-peptides, dyes and enzyme inhibitors. In a particular embodiment the ligand is biotin. The ligand can be chemically attached to the solid support as described in the examples where the chemical attachment of acarbose and reactive red 6 is illustrated.

[0152] The coupling of affinity ligands to supports strongly influences the specificity, capacity and cost of traditional affinity chromatography columns.

[0153] The current state of the art in covalent coupling technology allows for chemo and regio selective coupling of the binding ligands to the support, often using spacers or linkers to anchor the ligand to the surface.

[0154] Great care is taken to avoid using functional groups that are close to a binding site or that play a role in the interaction between the ligand and target molecule.

[0155] If a suitable functional group does not exist on the ligand, further derivatizing of the ligand can be done to add an appropriate functional group. Numerous references describe appropriate chemistries, including "Bioconjugate Techniques", by Greg T. Hermanson, Academic Press, 2008 and "Chemistry of Protein Conjugation and Cross-linking", by Shan S. Wong, CRC Press, 1991.

[0156] It is commonly accepted that a high concentration of coupled ligand often has adverse effects on affinity chromatography, also the binding efficiency of the medium may be reduced due to steric hindrance between the active sites. This is particularly pronounced when large molecules such as antibodies, antigens and enzymes interact with small ligands.

[0157] In addition, the target substances may become more strongly bound to closely packed ligands making elution difficult and also the extent of nonspecific binding increases at very high ligand concentrations, thus reducing the selectivity of the affinity column.

[0158] Ligand-surface interface interaction is known to be important for the affinity ligand performance. The length of spacer arms between the ligand and the surface is critical. If it is too short, the arm is ineffective and the ligand fails to bind the target in the sample. If it is too long, proteins may bind non-specifically to the spacer arm and reduce the selectivity of the separation. Often 4-12 atom long hydrophilic arms are used.

[0159] MabSelect® Media and HiTrap MabSelect® (GE Healthcare) are examples of affinity columns using oriented coupling of recombinant Protein A to the matrix via an engineered C-terminal cysteine and a hydrophilic spacer arm.

[0160] The present invention suggests the use of soluble dual affinity polypeptide which can be characterized and used in any concentration appropriate for the specific target concentration. The technical challenge of coupling delicate target specific binding ligands to a solid support is substituted with more simple preparation of soluble molecules making it possible to utilize the entire arsenal of analytical methods.

[0161] There are numerous types of support material for affinity chromotography.

[0162] The size and uniformity of beads, the distribution of internal channels and the nature of the surfaces has all been optimized to produce numerous types of supports.

[0163] In general, smaller particle size and greater porosity, ensures increased dynamic binding capacity. On the other hand, resistance to mechanical collapses is reduced.

[0164] Both compressible and the incompressible support material needs to be robust enough to survive multiple cycles without change of flow rates which will influence the residence time.

[0165] The solid support are in the form of beads, gels or granulates. The quality of packing of the solid support material in columns for traditional affinity purification and the flow rates during operation greatly influence the performance.

[0166] Specialized equipment is used to successfully pack large columns above 5-10 cm in diameter. High performance columns are normally purchased pre-packed and in standard sizes. Consequently, the practical dimensions during scale up depend on available column systems for the purification of the particular target molecule.

[0167] The present invention suggests a general method using target DAP molecules and a generic column.

[0168] One of the most important factors in determining the cost and quality of the large scale purification is the chemical and mechanical stability of the adsorbent.

[0169] Traditional affinity columns with immobilized protein ligands are susceptible to further degradation due to for example oxidation or microbial growth.

[0170] Therefore, due to the cost of large affinity columns, great care has to be taken to control the storage condition between uses. Often the column is washed and stored with a special buffer solution containing anti microbial agents, alcohols or similar. These storage solutions must be washed away before use.

[0171] Some affinity ligands are also sensitive to proteases and the column lifetime will be reduced unless special cleaning and regeneration procedures are followed rigorously. The freedom to design efficient affinity purification procedures is therefore somewhat restricted.

[0172] A single use column system according to the invention or a column system using synthetic ligands will not have the above technical limitations.

[0173] In one embodiment of the invention the solid support is in the form of a solid phase matrix. The solid phase matrix may comprise, as the matrix backbone, any natural or synthetic and organic or inorganic material known per se to be applicable in solid phase separation of proteins and other biomolecules, e.g. natural or synthetic polysaccharides such as agar-agar and agaroses; celluloses, cellulose ethers such as hydroxypropyl cellulose, carboxymethyl celluose; starches; gums such as guar gum, and gum arabic, gum ghatti, gum tragacanth, locust bean gum, xanthan gum; pectins; mucins; dextrans; chitins; chitosans; alginates; carrageenans; heparins; gelatins; synthetic polymers such as polyamides such as polyacrylamides and polymethacrylamides; polyimides; polyesters; polyethers; polymeric vinyl compounds such as polyvinylalcohols and polystyrenes; polyalkenes; inorganic materials such as silicious materials such as silicon dioxide including amorphous silica and quartz; silicas; metal silicates, controlled pore glasses and ceramics; metal oxides and sulfides, or combinations of these natural or synthetic and organic or inorganic materials.

[0174] The matrix backbone is preferably selected from agar-agar, agaroses, celluloses, cellulose ethers such as hydroxypropyl cellulose, carboxymethyl cellulose, polyamides such as poly(meth)acrylamides, polyvinylalcohols, silicas, and controlled pore glasses.

[0175] Especially interesting solid phase materials as matrix backbones are e.g. agar or agarose beads such as Sepharose and Superose beads from GE Healthcare, USA, and Biogel A from Biorad, USA; dextran based beads such as Sephadex, GE Healthcare; cellulose based beads and membranes such as Perloza cellulose from Iontosorb, Czech Republic; composite beads such as Sephacryl and Superdex, GE Healthcare, USA; beads of synthetic organic polymers such as Fractogel from Tosoh Lifesciences LLC, USA; POROS media from Applied Biosystems, USA, Bio-Rex, Bio-Gel P and Macro Prep from Biorad, HEMA and Separon from TESSEK and Hyper D and Trisacryl media from Pall Corporation, USA, Enzacryl and Azlactone, 3M, USA; beads of siliceous materials such as controlled pore glass, PROSEP, from Millipore, USA, and Spherocil, Pall Corporation, USA; and coated silica composites in the form of beads or membranes such as ACTI-DISK, ACTI-MOD and CycloSep from Arbor Technologies, USA.

[0176] The ligand (e.g. biotin or similar specific molecules of low molecular weight (LMW)) is then covalently attached to this material. Several coupling chemistries of ligand molecules to the solid support can be selected from text books on the subject (Protein Purifuication, 1998, 2ed, eds. Janson, J-C., Ryden, L, Wiley & sons inc. New York). Based on the particular purification task the best candidate of ligand derivatives is coupled to the best choice of solid support, e.g. solid phase matrix or particles. Production process properties of the affinity solid matrix are analyzed through practical laboratory and pilot testing.

[0177] The ligands may be attached to the solid phase material by any type of covalent bond known per se to be applicable for this purpose, either by a direct chemical reaction between the ligand and the solid phase material or by a preceding activation of the solid phase material or of the ligand with a suitable reagent known per se making it possible to link the matrix backbone and the ligand. Examples of such suitable activating reagents are epichlorohydrin, epibromohydrin, allyl glycidylether; bis-epoxides such as butanedioldiglycidylether; halogen-substituted aliphatic compounds such as di-chloro-propanol, divinyl sulfone; carbonyldiimidazole; aldehydes such as glutaric dialdehyde; quinones; cyanogen bromide; periodates such as sodium-meta-periodate; carbodiimides; chloro-triazines such as cyanuric chloride; sulfonyl chlorides such as tosyl chlorides and tresyl chlorides; N-hydroxy succinimides; 2-fluoro-1-methylpyridinium toluene-4-sulfonates; oxazolones; maleimides; pyridyl disulfides; and hydrazides. Among these, the activating reagents leaving a spacer group SP1 different from a single bond, e.g. epichlorohydrin, epibromohydrin, allylglycidylether; bis-epoxides; halogen-substituted aliphatic compounds; divinyl sulfone; aldehydes; quinones; cyanogen bromide; chloro-triazines; oxazolones; maleimides; pyridyl disulfides; and hydrazides, are preferred.

[0178] In one embodiment the solid support is in the form of particles. Particles can be selected from the group comprising microspheres, latex particles or beads. The particles can be made from but not limited to the group consisting of e.g. polystyrene, silica, naphtaleen, polybutylmethacrylate.

[0179] The generic solid support can be produced at costs comparable to ion exchange matrices and the recombinant dual affinity protein can also be produced as a recombinant fusion protein by fermentation at low cost. Due to the lowered cost of the novel downstream procedure materials, the purification technology may be provided as disposables, which eliminate the need for expensive cleaning in place (CIP) and certain validations. Another consequence of the reduced cost is optional large column-volume applications, which saves manufacturing labour expenses, prevent repeated purification re-runs and limit time occupations of the downstream process plant.

[0180] The use of a generic solid support including the capturing ligand and the potentially improved binding efficiency and capacity due to complex formation in solution poses several advantages over the conventional affinity chromatography. These advantages are listed below. [0181] No time consuming and expensive chemical conjugation reactions, purifications and QC procedures of protein ligands to prepare the affinity column material prior to affinity purification of the target molecule. [0182] The generic matrix is more cost efficient to manufacture compared to the present commercial affinity matrices matrices (e.g. Protein A). Only one type of capturing column material is required for all affinity purifications using the dual affinity polypeptide principle. The low molecular weight ligand, e.g. biotin, dye molecules or similar specific low molecular weight (LMW) molecules are covalently attached by simple low cost conjugation procedures to make the generic solid phase matrix. [0183] The preferred fermentation of a dual affinity polypeptide fusion protein is "simple", based on known technology and provide the conjugation needed between binding domains in DAP [0184] The manufacturing cost of DAP molecules is comparable or cheaper than recombinant Protein A molecules. [0185] The DAP fusion protein and the generic matrix required for purification purposes costs a fraction of the ready-to-use Protein A affinity matrix for similar purposes [0186] The DAP transport and immobilize the target molecules to the generic matrix during the purification process. The is no need for an expensive and time consuming immobilization of a dedicated ligand to make an specific purification matrix as known in conventional affinity chromatography. [0187] The low cost of the components in the presented invention facilitate a disposable affinity purification process featuring [0188] elimination of CIP procedures [0189] elimination of validation procedures [0190] save time on regulatory issues [0191] exclude repetitions of down stream process cycles [0192] limit operational failures [0193] lower labor expenses during processing [0194] shorter manufacturing run time [0195] limit risk of contamination [0196] easy to use [0197] lower capacity cost investments due to flexible plant designs [0198] better down stream process economy [0199] Substitution of conventional multi-cycle protein separation procedures to a single step using the disposable affinity purification technology.

[0200] In a particular modified form of the invention it could be envisioned that the DAP molecule could bind covalently to the solid support. This would still allow the possibility of having the DAP and the target reacting in solution. Such a covalent bond could in one embodiment be formed by cleavage of a para-substituted benzyl guanine resulting in a thioether bond.

[0201] One embodiment of this modified form of the invention therefore relates to a process for purification of a target biomolecule, comprising the steps: (a) contacting (i) a target polypeptide, (ii) a dual affinity polypeptide, and (iii) a solid support comprising a catching ligand, wherein the dual affinity polypeptide has an equilibrium dissociation constant, K_D,t towards the target biomolecule in the range from 10^-2 to 10^-13 M, more particularly from 10^-4 to 10^-13 M at standard conditions, and wherein binding of the dual affinity polypeptide to the catching ligand on the solid support is provided by cleavage of a para-substituted benzyl guanine resulting in a thioether bond; and (b) recovering the target biomolecule by elution.

[0202] The basic principle of the affinity purification technology, for purifying a target molecule (polyclonal antibody) is illustrated below.

EXAMPLES

Example 1

Preparation of Dual Affinity Linker by Chemical Conjugation

[0203] Based on published values for binding affinities, dual linker binding functionalities were selected that fit both to the binding to the ligand matrix (K_D,s˜10^-9 to 10^-16M) and to the target biomolecules (products, K_D,t˜10^-2 to 10^-13 M). To investigate the influence of the K_D,s, some components with K_D,s-values outside the above interval were also tested.

[0204] In order to prepare a conjugate made from Protein A and a biotin binding protein e.g. Avidin, Streptavidin or Neutravidin the two proteins were chemically activated separately as a first step and joined together by cross linking in a second step afterwards.

[0205] Protein A do not have accessible sulphydryl (--SH) on the surface, so these were introduced be reaction with SATA (N-succinimidyl S-acetylthioacetate) to primary amine (--NH2) functional groups on Protein A. SATA (or SATP) is a reagent for introducing protected sulfhydryls into proteins, peptides and other molecules. They are the N-hydroxysuccinimide (NHS) esters of S-acetylthioacetic and propionic acid. A stable, covalent amide bond was formed from the reaction of the NHS ester with primary amines. The amine was reacted with the NHS ester by nucleophilic attack, with N-hydroxysuccinimide being released as a by-product. Deprotection (deacylation) to generate a sulfhydryl for use in cross-linking and other applications was accomplished using hydroxylamine.HCl.

[0206] The maleimide groups were introduced to the Avidin using Sulfo-SMCC. Sulfo-SMCC is a heterobifunctional cross-linker that contains a N-hydroxysuccinimide (NHS) ester and a maleimide group. NHS esters react with primary amines at pH 7-9 to form covalent amide bonds. SMCC and Sulfo-SMCC are often used to prepare protein-protein conjugates in a two-step reaction scheme. First, the amine-containing protein was reacted with a several-fold molar excess of the cross linker, followed by removal of excess (nonreacted) reagent by desalting or dialysis; finally, the sulfhydryl-containing molecule is added to react with the maleimide groups already attached to the first protein.

[0207] The conjugates prepared by cross linking were obtained by reacting maleimides with sulphydryl groups at pH 6.5-7.5 to form stable thioether bonds.

[0208] An alternative to the procedure above is to use commercially available Malimide activated Neutravidin instead of the activated Avidin. Maleimide Activated NeutrAvidin® Protein is for directly preparing NeutrAvidin® Protein (NAP) conjugates with proteins, peptides, and other molecules that contain a free sulfhydryl (--SH) group.

Preparation of Dual Affinity Polypeptide (DAP) by Chemical Cross-Linking

[0209] Procedure for chemically cross-linking Protein A, and either Avidin or Neutravidin into a conjugate with the required properties of a DAP linker.

Materials

[0210] SATA (N-Succinimidyl S-Acetylthioacetate), (Pierce, no. 26102) D-Salt® Excellulose® Desalting Column, 5 ml (Pierce No. 20449)

[0211] Hydroxylamine.HCl (Pierce, No. 26103), DMSO (Dimethylsulfoxide, Pierce, No. 20688), Sulfo-SMCC: (sulfosuccinimidyl 4-(N-maleimidomethyl)cyclohexan-1-carboxylate) (Pierce, 22322), Protein A (GE Health Care, 17-0872-50), Avidin (Kem-En-Tec, 4020H), Maleimide activated neutravidin (Pierce, no. 31007), PD-10 Sephadex G-25M (GE; 17-0851-01),

[0212] HiPrep 26/60 Sephacryl S-100 HR (MW range 1.000-100.000) (GE, 17-1194-01)

[0213] Anti-IgG Affibody (Affibody, 10.0623.01.0050)

[0214] Dithiothreitol ([3483-12-3], Sigma-Aldrich D0632).

Buffers:

[0215] PBS Reaction Buffer: 200-500 ml of PBS: 0.1 M phosphate, 0.15 M NaCl, pH 7.2

[0216] Deacetylation Solution: 0.5 M Hydroxylamine, 25 mM EDTA in PBS, pH 7.2

[0217] PBS-EDTA solution: 200-500 ml of PBS: 0.1 M phosphate, 0.15 M NaCl, 5 mM EDTA, pH 7.2.

[0218] Phosphate-buffered saline (PBS, pH 7.2; or other amine- and sulfhydryl free buffer at pH 6.5-7.5 adding EDTA to 1-5 mM helps to chelate divalent metals, thereby reducing disulfide formation in the sulfhydryl-containing protein.

Procedure for Sulfhydryl Modification of Protein A

[0219] A. Reaction of Protein A with SATA (or SATP)

[0220] Immediately before reaction, 6.4 mg of SATA was dissolved in 0.5 ml of DMSO (resulting in ˜55 mM solution).

[0221] 1.0 ml of Protein A solution (2.6 mg/mL) was then combined with 10 μl of the SATA solution. The contents were mixed and incubated at room temperature for 30 minutes.

[0222] The level of sulfhydryl incorporation may be altered by using different molar ratios of SATA to protein. The default reaction uses 60 nmol Protein A and 550 nmol SATA, a 9:1 molar ratio of SATA to protein. The amount of SATA in the reaction may be increased or decreased by adding more or less than 10 μl of the SATA solution per ml of Protein Solution.

B. Desalt to Purify Acylated Protein A from Excess Reagent and by-Products

[0223] A desalting column was equilibrated with two column volumes of Reaction Buffer. Use at least a 5 ml desalting column for each 1 ml of reaction volume to be processed.

[0224] 1.01 ml reaction mixture was applied to the column. Collection of 1 ml fractions was started immediately. After the reaction mixture had completely entered the column bed and the first fraction was collected, at least 10 mL Reaction Buffer was added to the column and collection continued as separate 1 ml fractions as they emerged from the column.

[0225] Fraction(s) that contain Protein A were identified as those having peak absorbance at 280 nm. With a 5 ml desalting column, fractions 2 and 3 contained most of the protein, while excess SATA came out in the following fractions. The fractions that contain the modified Protein A were pooled.

[0226] The modified Protein A may be stored indefinitely for later deacetylation and generation of sulfhydryl groups (Section C).

C. Deacetylate SATA-Modified Protein A to Generate Sulfhydryl Groups

[0227] 1.0 ml of SATA-modified (acetylated) Protein A was combined with 100 μl of the Deacetylation Solution. The contents were mixed and incubated 2 hours at room temperature.

[0228] A desalting column was used to purify the sulfhydryl-modified protein from the Hydroxylamine in the Deacetylation Solution.

[0229] Desalting was done into Reaction Buffer containing 10 mM EDTA to minimize disulfide bond formation using the same procedure as in Section B. Fractions that contained the modified ProteinA were pooled. The protein concentration should be ˜1.3 mg/ml. In order to minimize disulfide formation Section D was performed immediately.

[0230] Before or after desalting, the protein may be assayed for sulfhydryl content using Ellman's Reagent (Pierce, no 23460 (kit for sulfhydryl group detection)).

D. Conjugation of SATA modified Protein A to Maleimide Activated Avidin or Neutravidin.

[0231] This method uses approximately equimolar amounts of activated Protein A to Avidin or Neutravidin.

Example 1a

Procedure for Maleimide Modification of Avidin and Preparation of the DAP molecule [Protein A--Avidin]

[0232] Generally, a 10- to 50-fold molar excess of cross-linker over the amount of amine-containing protein results in sufficient maleimide activation to enable several sulfhydryl-containing proteins to be conjugated to each amine-containing protein.

[0233] More dilute protein solutions require greater fold molar excess of reagent to achieve the same activation level. Empirical testing is necessary to determine optimal activation levels and final conjugation ratios for the intended application.

Protocol

[0234] For best results, ensure that Protein A-SH is prepared as described above and ready to combine with maleimide activated Avidin in step 5.

[0235] 32 mg Avidin was prepared in 5 mL PBS Buffer, and 4.36 mg sulfo-SMCC was prepared in 1 mL PBS/EDTA buffer. Then 500 μL of the activation solution was transferred to the Avidin solution. The mixture was incubated 30 minutes at room temperature. Excess cross-linker was remove using a desalting column equilibrated with PBS-EDTA Buffer.

[0236] Protein A-SH and desalted maleimid activated Avidin were combined and mixed in a molar ratio corresponding to approximately 1:1. The reaction mixture was incubated at room temperature overnight.

[0237] Generally, there is no harm in allowing the reaction to proceed for several hours or overnight, although usually the reaction will be complete in about 30 min. To stop the conjugation reaction before completion, add buffer containing reduced cysteine at a concentration several times greater than the sulfhydryls of Protein A-SH.

Example 1b

Preparation of the DAP Molecule [Protein A--Neutravidin]

[0238] For best results, ensure that Protein A-SH is prepared as described above and ready to combine with maleimide activated Avidin.

[0239] Maleimide activated Neutravidin (Pierce, no 31007) is commercially available for directly preparing NeutrAvidin® Protein (NAP) conjugates with proteins, peptides, and other molecules that contain a free sulfhydryl (--SH) group. NeutrAvidin® Protein is a modified avidin derivative with several key features that provide a biotin-binding protein with exceptionally low non-specific binding properties. NeutrAvidin® Protein does not contain carbohydrates, rendering lectin-binding activity to undetectable levels. Additionally, the isoelectric point of NAP is 6.3±0.3, which is much lower than native Avidin and not as acidic as streptavidin.

Protocol

[0240] 1.0 mL of ultra pure water was added to suspend 5 mg lyophilized Neutravidin.

[0241] Protein A-SH and maleimid activated Neutravidin were combined and mixed in a molar ratio corresponding to 1:1. The reaction mixture was incubated at room temperature overnight.

[0242] Generally, there is no harm in allowing the reaction to proceed for several hours or overnight, although usually the reaction will be complete in the specified time. To stop the conjugation reaction before completion, add buffer containing reduced cysteine at a concentration several times greater than the sulfhydryls of Protein A-SH.

Example 1c

Preparation of the DAP Molecule [Affibody (IgG)--Avidin]

Protocol

[0243] Avidin (10 mg) was activated with sulfo-SMCC as described in Example 1a.

[0244] Anti-IgG Affibody disulfide dimers were reduced to monomers:

[0245] Anti-IgG Affibody (5 mg) is dissolved in PBS-buffer (5 mL), and 3.8 mL of this solution is transferred to a vial containing 12.3 mg dithiothreitol (DTT) giving a final DTT concentration of 20 mM solution. This mixture is turned at RT for 2 h.

[0246] Upon this, excess DTT is removed by splitting the reaction mixture in two portions, passing each portion through a PD-10 column (bedvolume 8 mL). The columns had been equilibrated with 25 mL PBS buffer before use. The monomeric Anti-IgG Affibody is eluted from the columns in 2×9-10 fractions, each containing 1 mL.

[0247] By measuring A₂₈₀ of the fractions the protein was located in 2 fractions from each column. These fractions were pooled and mixed with the desalted maleimid activated avidin solution (20 mL) in a molar ratio corresponding to approximately 1:1 (avidin calculated as monomer; MW=17.000), and the coupling was allowed to proceed overnight at room temperature with gently turning of the coupling mixture.

[0248] The following day, 1500 μL of the conjugation mixture was concentrated in an Amicon Ultra (cut off 3 kDa) to a total volume of 400 μL, which was used for analysis by SDS PAGE. This showed that all avidin had reacted, and that there was still some unreacted anti-IgG Affibody present.

[0249] The conjugation mixture was freezed until purified by SEC.

[0250] The above protocol can be used for the preparation of all derivatives of Affibody-Avidin dual affinity polypeptides.

Example 1d

Preparation of the DAP Molecule [Affibody (Insulin)--Avidin]

[0251] Avidin (9 mg) was activated with sulfo-SMCC as described in Example 1a.

[0252] Anti-Insulin Affibody (His₆-Z000810-Cys; P800014) disulfide dimers were reduced to monomers as described in Example 1c.

[0253] The pooled fractions from the PD-10 columns were mixed with the desalted maleimid activated avidin solution (16.1 mL) in a molar ratio corresponding to approximately 1:1, and the coupling was allowed to proceed overnight at room temperature with gently turning of the coupling mixture.

[0254] The following day, the conjugation mixture was analyzed by SDS PAGE. This showed that all avidin had reacted, and that there was still some unreacted anti-Insulin Affibody present.

[0255] The conjugation mixture was freezed until purified by SEC.

Example 1e

Preparation of the DAP Molecule [Affibody (Insulin)--Avidin]

[0256] Avidin (9 mg) was activated with sulfo-SMCC as described in Example 1a.

[0257] Anti-Insulin Affibody (Insulin, His₆-Z01139-Cys; P800022) disulfide dimers were reduced to monomers as described in Example 3c.

[0258] The pooled fractions from the PD-10 columns were mixed with the desalted maleimid activated avidin solution (16.1 mL) in a molar ratio corresponding to approximately 1:1, and the coupling was allowed to proceed overnight at room temperature with gently turning of the coupling mixture.

[0259] The following day, the conjugation mixture was analyzed by SDS PAGE. This showed that all avidin had reacted, and that there was still some unreacted anti-Insulin Affibody present.

[0260] The conjugation mixture was freezed until purified by SEC.

Example 2

Recombinant Dual Affinity Constructs for Expression in Aspergillus oryzae

Strains

[0261] Aspergillus oryzae BECh2 is described in WO 00/39322, example 1, which is further referring to JaL228 described in WO 98/12300, example 1.

[0262] JaL1168 is described in example 2 g.

[0263] JaL1171 is described in example 2 g.

[0264] JaL1174 is described in example 2 g.

[0265] JaL1176 is described in example 2 g.

[0266] JaL1181 is described in example 2 g.

[0267] JaL1210 is described in example 2 g.

[0268] MT173 is a derivative of MC1000 (Casadaban & Cohen J. Mol. Biol. 138 (1980) 179-207) which are ara.sup.+ and leuB6.

Genes

[0269] AMG: indicate the Aspergillus niger glucoamylase gene (Boel et al. EMBO Journal 3 (1984) 1581-1585)

[0270] Z: indicated the Z domain from Staphylococcus aureus protein A (Nilsson et al. Protein Engineering 1 (1987) 107-113).

[0271] Pre-CBD.sub.(C315): indicate the Meripilus giganteus endoglucanase II (DSM971) signal (pre)+cellulose binding domain (CBD)+linker region.

[0272] CBD(egv): indicated the Humicola insulens endoglucanase V (DSM1800) linker region+cellulose binding domain.

[0273] VhhRR6(2): indicated the variable region from a Llama single chain antibody reacting against the hapten azo-dye Reactive Red (RR6) (Frenken et al. J. Biotechnology 78 (2000) 11-21.

Plasmids

[0274] p775 is described in EP 238023.

[0275] pA2C315 is deposited at DSM under the accession no. DSM971. The plasmid contains a cDNA clone from Meripilus giganteus encoding an endoglucanase II gene.

[0276] pCAMG91 is described in Boel et al. EMBO Journal 3 (1984), 1581-1585.

[0277] pJaL790 is described in WO2005070962, example 1.

[0278] pJaL1153 is described in example 2c.

[0279] pJaL1154 is described in example 2a.

[0280] pJaL1158 is described in example 2d.

[0281] pJaL1159 is described in example 2a.

[0282] pJaL1164 is described in example 2c.

[0283] pJaL1165 is described in example 2d.

[0284] pJaL1168 is described in example 2e.

[0285] pJaL1169 is described in example 2b.

[0286] pJaL1170 is described in example 2f.

[0287] pJaL1171 is described in example 2b.

[0288] pMT2786 is described in WO2006050737 example 2.

[0289] pSX320 is described in EP 0 531 372.

Primer and DNA Sequences

[0290] Synthetic DNA 1 (SEQ ID NO 1)

[0291] Synthetic DNA 2 (SEQ ID NO 4)

[0292] Adaptor sequence 1 (SEQ ID NO 5)

[0293] Adaptor sequence 2 (SEQ ID NO 6)

[0294] primer 8683 (SEQ ID NO 10)

[0295] primer CBD:Z-NA (SEQ ID NO 11)

[0296] primer Z-NA (SEQ ID NO 12)

[0297] primer Z-CA (SEQ ID NO 13)

[0298] primer Z-CA:CBD (SEQ ID NO 14)

[0299] primer 8654 (SEQ ID NO 15)

[0300] Primer CBD:Z-NB (SEQ ID NO 19)

[0301] Primer Z-NB (SEQ ID NO 20)

[0302] Primer Z-CB (SEQ ID NO 21)

[0303] Primer Z-NB:CBD (SEQ ID NO 22)

Methods

[0304] General methods of PCR, cloning, ligation nucleotides etc. are well-known to a person skilled in the art and may for example be found in "Molecular cloning: A laboratory manual", Sambrook et al. (1989), Cold Spring Harbor lab., Cold Spring Harbor, N.Y.; Ausubel, F. M. et al. (eds.); "Current protocols in Molecular Biology", John Wiley and Sons, (1995); Harwood, C. R., and Cutting, S. M. (eds.); "DNA Cloning: A Practical Approach, Volumes I and II", D. N. Glover ed. (1985); "Oligonucleotide Synthesis", M. J. Gait ed. (1984); "Nucleic Acid Hybridization", B. D. Hames & S. J. Higgins eds (1985); "A Practical Guide To Molecular Cloning", B. Perbal, (1984).

PCR Amplification

[0305] All PCR amplifications were performed in a volume of 100 microL containing 2.5 units Tag polymerase, 100 ng of pSO2, 250 nM of each dNTP, and 10 μmol of each of the two primers described above in a reaction buffer of 50 mM KCl, 10 mM Tris-HCl pH 8.0, 1.5 mM MgCl2. Amplification was carried out in a Perkin-Elmer Cetus DNA Termal 480, and consisted of one cycle of 3 minutes at 94° C., followed by 25 cycles of 1 minute at 94° C., 30 seconds at 55° C., and 1 minute at 72° C.

Aspergillus Transformation

[0306] Aspergillus transformation was done as described by Christensen et al.; Biotechnology 1988 6 1419-1422. In short, A. oryzae mycelia were grown in a rich nutrient broth. The mycelia were separated from the broth by filtration. The enzyme preparation Novozyme® (Novo Nordisk) was added to the mycelia in osmotically stabilizing buffer such as 1.2 M MgSO₄ buffered to pH 5.0 with sodium phosphate. The suspension was incubated for 60 minutes at 37 degrees C. with agitation. The protoplast was filtered through mira-cloth to remove mycelial debris. The protoplast was harvested and washed twice with STC (1.2 M sorbitol, 10 mM CaCl₂, 10 mM Tris-HCl pH 7.5). The protoplasts were finally re-suspended in 200-1000 microl STC.

[0307] For transformation, 5 microg DNA was added to 100 microl protoplast suspension and then 200 microl PEG solution (60% PEG 4000, 10 mM CaCl₂, 10 mM Tris-HCl pH 7.5) was added and the mixture is incubated for 20 minutes at room temperature. The protoplast were harvested and washed twice with 1.2 M sorbitol. The protoplast was finally resuspended 200 microl 1.2 M sorbitol. Transformants containing an intact niaD gene were selected for its ability to used nitrate as the sole source for nitrogen on minimal plates (Cove D. J. 1966. Biochem. Biophys. Acta. 113:51-56) containing 1.0 M sucrose as carbon source, 10 mM Sodium nitrate as nitrogen source. After 4-5 days of growth at 37 degrees C., stable transformants appeared as vigorously growing and sporulating colonies. Transformants were purified twice through conidiospores.

Media and Reagents

[0308] YPM medium (2 g/l yeast extract, 2 g/l peptone, and 2% maltose)

Growth of Aspergillus Transformants

[0309] Shake flask containing 10 ml YPM medium was inoculated with spores from the respective transformants and incubated at 30 degrees C., at 200 rpm for 4 days.

SDS-Page

[0310] SDS gel used was Criterion® XT precast gels, 10% Bis-Tris, from BIO-RAD and was run and stained with Coomassie blue as recommend by the manufactory.

Example 2a

Construction of Aspergillus Expression Cassette pJaL1159 (Pre-CBD.sub.(C315)-KR::VhhRR6(R2)::Z::Z)

[0311] Plasmid pJaL1154 contains a synthetic DNA SEQ ID NO 1 in pUC19 encoding a fusion protein composed of: signal+cellulose binding domain+linker from C315, the amino acids KR, the variable region of a llama single chain antibody raised against the reactive dye RR6, and a repeat of the Z domain from protein A (pre-CBD.sub.(C315)-KR::VhhRR6(R2)::Z::Z).

[0312] Expression vector pJaL1159 was constructed for transcription of the fusion protein pre-CBD.sub.(C315)-KR::VhhRR6(R2)::Z::Z (SEQ ID NO 2). The plasmid pJaL1154 harboring the fusion protein was digested with BamHI-XhoI. The 966 bp fragment was gel-purified and ligated into the Aspergillus expression cassette pMT2786 digested with BamH I-XhoI (a 6936 bp fragment). The ligation mixture was transformed into E. coli MT173 using the Saccharomyces cerevisiae Leu2 gene as selective marker to create the expression plasmid pJaL1159. The amplified plasmid was recovered using a QIAprep® Spin Miniprep kit (QIAGEN, Chatsworth, Calif.) according to the manufacturer's instructions

[0313] Plasmid pMT2786 comprise an expression cassette based on the Aspergillus niger neutral amylase II promoter fused to the Aspergillus nidulans triose phosphate isomerase non translated leader sequence (Na2/tpi promoter) and the Aspergillus niger amyloglycosidase terminator (AMG terminator), the selective marker amdS from Aspergillus nidulans enabling growth on acetamide as nitrogen source and having the Saccharomyces cerevisiae Leu2 gene for selection in E. coli.

Example 2b

[0314] Construction of Aspergillus Expression Cassette pJaL1171 Pre-CBD.sub.(C315)KR::VhhRR6(R2)::Z

[0315] For construction of the fusion protein pre-CBD.sub.(C315)-KR::VhhRR6(R2)::Z (SEQ ID NO 3) plasmid pJaL1154 was digested with BglII and the 3472 bp fragment was gel-purified and ligated with itself resulting in pJaL1169. The 795 bp BamHI-XhoI fragment from pJaL1169 was purified and ligated into the Aspergillus expression cassette pMT2780 digested with BamH I and XhoI (a 6936 bp fragment). The ligation mixture was transformed into E. coli MT173 using the Saccharomyces cerevisiae Leu2 gene as selective marker to create the expression plasmid pJaL1171. The amplified plasmid was recovered using a QIAprep® Spin Miniprep kit (QIAGEN, Chatsworth, Calif.) according to the manufacturer's instructions.

Example 2c

[0316] Construction of Aspergillus Expression Cassette pJaL1164 AMG.sub.(1-526aa)::Z::Z

[0317] Plasmid pJaL1153 contains a synthetic DNA SEQ ID NO 4 in pUC19 encoding a fusion protein composed of: Aspergillus niger AMG DNA encoding amino acids 488-526 and a repeat of the Z domain from protein A (AMG.sub.(488-526aa)::Z::Z).

[0318] Plasmid pToC100 contains the Aspergillus niger AMG (Boel et al. EMBO Journal 3 (1984), 1581-1585) regulated by the TAKA promoter from p775 and at the same time a BamHI site was introduce upfront of the AMG start codon. pToC100 was constructed by ligating the following fragments together: 4306 bp BamHI-NcoI fragment from p775, an adapter SEQ ID NO: 5 and SEQ ID NO.: 6, 860 bp BssHII-Pst1 from pCAMG91 and 1410 bp PstI-NcoI fragment from pCAMG91.

[0319] Expression vector pJaL1164 was constructed for transcription of the fusion protein AMG.sub.(1-526aa)::Z::Z (SEQ ID NO 7). A 1723 bp BamHI-DraIII fragment and a 458 bp DraIII-XhoI fragment was gel-purified from plasmid pToC100 and pJaL1153, respectively, and ligated into the Aspergillus expression cassette pMT2786 digested with BamH 1-XhoI (a 6936 bp fragment). The ligation mixture was transformed into E. coli MT173 using the Saccharomyces cerevisiae Leu2 gene as selective marker to create the expression plasmid pJaL1164. The amplified plasmid was recovered using a QIAprep® Spin Miniprep kit (QIAGEN, Chatsworth, Calif.) according to the manufacturer's instructions.

Example 2d

Construction of Aspergillus Expression Cassette pJaL1165 AMG.sub.(1-526aa)::Z

[0320] For construction of an expression plasmid encoding for the fusion protein AMG.sub.(1-526aa)::Z (SEQ ID NO 8) plasmid pJaL1153 was digested with BglII and the 2969 bp fragment was gel-purified and ligated with itself resulting in pJaL1158. A 1723 bp BamHI-DraIII fragment from pToC100 and a 287 bp fragment from pJaL1158 was purified and ligated into the Aspergillus expression cassette pMT2786 digested with BamH I and XhoI (a 6936 bp fragment). The ligation mixture was transformed into E. coli MT173 using the Saccharomyces cerevisiae Leu2 gene as selective marker to create the expression plasmid pJaL1165. The amplified plasmid was recovered using a QIAprep® Spin Miniprep kit (QIAGEN, Chatsworth, Calif.) according to the manufacturer's instructions.

Example 2e

Construction of Aspergillus Expression Cassette pJaL1168 Pre-CBD.sub.(C315)::Z::Z::CBD.sub.(egv)

[0321] Construction of the expression plasmid pJaL1168 encoding for the fusion protein pre-CBD.sub.(C315)::Z::Z::CBD.sub.(EGV) (SEQ ID NO 9) was done by amplification by PCR: 1) of the pre-CBD.sub.(C315) region using pA2C315 as template and the primer pair 8683/CBD:Z-NA (SEQ ID NO 10 and 11), 2) of the Z::Z region using pJaL1153 as template and the primer pair Z-NA/Z-CA (SEQ ID NO 12 and 13) and 3) of the CBD.sub.(EGV) region using pSX320 as template and the primer pair Z-CA:CBD/8654 (SEQ ID NO 14 and 15), resulting in 3 DNA fragments of 337 bp, 382 bp and 344 bp, respectively. The 3 fragments were mixed and used as template for amplification by PCR with primer pair 8653/8654 of a 983 bp fragment. The PCR fragment was digested with BamHI-HindIII and the 798 bp fragment was purified and clone ligated into the Aspergillus expression cassette pJaL790 digested with BamH I-HindIII (a 7386 bp fragment). The ligation mixture was transformed into E. coli DB6507 using the Saccharomyces cerevisiae Ura3 gene as selective marker to create the expression plasmid pJaL1168. The amplified plasmid was recovered using a QIAprep® Spin Miniprep kit (QIAGEN, Chatsworth, Calif.) according to the manufacturer's instructions.

[0322] Plasmid pJaL790 comprised an expression cassette based on the Aspergillus niger neutral amylase II promoter fused to the Aspergillus nidulans triose phosphate isomerase non translated leader sequence (Na2/tpi promoter) and the Aspergillus niger amyloglycosidase terminator (AMG terminator), the selective marker amdS from Aspergillus oryzae enabling growth on acetamide as nitrogen source.

Example 2f

Construction of Aspergillus Expression Cassette pJaL1170 Pre-CBD.sub.(C315)-KR::Z::Z::CBD.sub.(C315)::CBD.sub.(EGV)

[0323] Plasmid pJaL802 is an Aspergillus expression plasmid builds on pJaL790 which contains a DNA (SEQ ID NO 16) encoding for the fusion protein pre-CBD.sub.(C315)::CBD.sub.(EGV) (SEQ ID NO 17).

[0324] Construction of the expression plasmid pJaL1170 encoding for the fusion protein pre-CBD.sub.(C315)-KR::Z::Z::CBD.sub.(C315)::CBD.sub.(EGV) (SEQ ID NO 18) was done by amplification by PCR: 1) of the pre-CBD.sub.(C315)-KR region using pA2C315 as template and the primer pair 8683/CBD:Z-NB (SEQ ID NO 10 and 19), 2) of the Z::Z region using pJaL1153 as template and the primer pair Z-NB/Z-CB (SEQ ID NO 20 and 21) and 3) of the CBD.sub.(C315)-CBD.sub.(EGV) region using pJaL802 as template and the primer pair Z-CB:CBD/8654 (SEQ ID NO 22 and 15), resulting in 3 DNA fragments of 343 bp, 382 bp and 443 bp, respectively. The 3 fragments were mixed and used as template for amplification by PCR with primer pair 8653/8654 of a 1088 bp fragment. The PCR fragment was digested with BamHI-HindIII and the 894 bp fragment was purified and clone ligated into the Aspergillus expression cassette pJaL790 digested with BamH I-HindIII (a 7386 bp fragment). The ligation mixture was transformed into E. coli DB6507 using the Saccharomyces cerevisiae Ura3 gene as selective marker to create the expression plasmid pJaL1170. The amplified plasmid was recovered using a QIAprep® Spin Miniprep kit (QIAGEN, Chatsworth, Calif.) according to the manufacturer's instructions,

Example 2g

Expression of DAP in Aspergillus oryzae Strains

[0325] The Aspergillus oryzae strains BECh2 was transformed with the expression plasmid pJaL1159, pJaL1164, pJaL1165, pJaL1168, pJaL1170 and pJaL1171 as described under methods.

[0326] A shake flask containing 10 ml YPM medium (2 g/l yeast extract, 2 g/l peptone, and 2% maltose) was inoculated with spores from the generated transformants and the host BECh2 and incubated at 30° C., with shaking (200 rpm) for 4 days. Supernatants (10 μl) were analysed on SDS-page. A transformant producing the desired protein from each plasmid pJaL1159, pJaL1164, pJaL1165, pJaL1168, pJaL1170 and pJaL1171 was named JaL1210, JaL1168, JaL1171, JaL1174, JaL1176 and JaL1181, respectively. Products of the expected size from each transformant were confirmed by SDS-page. The amino acids sequence of each construct produced in JaL1210 (VhhRR6(R2)::Z::Z), JaL1168 (AMG.sub.(1-526aa)::Z::Z), JaL1171 (AMG.sub.(1-526aa)::Z), JaL1174 (CBD.sub.(C315)::Z::Z::CBD.sub.(egv)), JaL1176 (Z::Z::CBD.sub.(C315):: CBD.sub.(egv)) and JaL1181 (VhhRR6(R2)::Z) are shown in SEQ ID NO 23, SEQ ID NO 24, SEQ ID NO 25, SEQ ID NO 26, SEQ ID NO 27 and SEQ ID NO 28, respectively.

Example 3

Recombinant Dual Affinity Constructs for Expression in Bacillus licheniformis

Media

[0327] LB agar, TY buillon medium and BPX shake flask medium have all been described in Patent Publication WO 94/14968.

[0328] CAL 18-2 media (11): Yeast extract (#0127-17-9 Difco Laboratories, MI, USA) 40 g; Magnesium Sulfate (#5886 Merck, Darmstadt, Germany) 1.3 g; Glucidex 12 (Roquette Feres, France) 50 g; Sodium Di-hydrogenphosphate (#6346 Merck, Darmstadt, Germany) 20 g; EDF-Tracemetals (recipe see below) 6.7 ml; Na₂MoO₄-Tracemetals (recipe see below) 6.7 ml; Pluronic PE6100 (BASF, Germany) 0.1 ml; Ionexchanged water adjust to 1000 ml. All is mixed, volume is adjusted, pH is measured and adjusted to pH 6.0 using NaOH. The media is sterilised by aotoclaving at 121° C. for 20 min. EDF-Tracemetals (11): Mangan (II) sulphate (#5963 Merck, Darmstadt, Germany) 4.48 g; Iron (III) chloride (#3943 Merck, Darmstadt, Germany) 3.33 g; Copper (II) sulphate (#2790 Merck, Darmstadt, Germany) 0.625 g; Zinksulphate (#8883 Merck, Darmstadt, Germany) 7.12 g; Ionexchanged water adjust to 1000 ml. All is mixed, volume is adjusted. Solution is filter-sterilized and kept at 4° C. Na₂MoO₄-Tracemetals (11): SodiumMolybdat (#6521 Merck, Darmstadt, Germany) 2.0 g; Ionexchanged water adjust to 1000 ml. All is mixed, volume is adjusted. Solution is filtersterilized and kept at 4° C.

Strains and Donor Organisms

[0329] Bacillus subtilis PL1801. This strain is the B. subtilis DN1885 with disrupted apr and npr genes (Diderichsen, B., Wedsted, U., Hedegaard, L., Jensen, B. R., Sjoholm, C. (1990) Cloning of aldB, which encodes alpha-acetolactate decarboxylase, an exoenzyme from i Bacillus brevis. J. Bacteriol., 172, 4315-4321).

[0330] Bacillus subtilis PP289-5. This strain is a donor strain for conjugation of plasmids to Bacillus licheniformis described in U.S. Pat. No. 5,843,720

[0331] Bacillus licheniformis MDT223 described in patent WO2005/123915

Genes

[0332] Z: indicate the Z domain from Staphylococcus aureus protein A (Nilsson et al. Protein Engineering 1 (1987) 107-113). The Z gene is a synthetic gene assembled by primers (SEQ ID NO 29)

[0333] Streptavidin gene: indicate the gene encoding Streptavidin from Streptomyces avidinii as described by Argarana (Argarana et. Al. (1986) Nucleic Acids Res. 14, 1871-1882). The gene encoding streptavidin is a synthetic gene (SEQ ID NO 30)

[0334] A synthetic gene can be constructed by PCR assembly of overlapping oligonucleotides in various methods described eg. by Stemmer et al, Gene 164, pp-49-53, 1995; Dillon and Rossen, BioTechniques 9, 298-300, 1990; Prodromou and Pearl, Protein Engineering 5, 827-829, 1992; Chn et al., Journal of Amarican Chemical Society 11, 8799-8800, 1994 and others. Such genes may also simply be purchased through one of many commercial companies.

Plasmids

[0335] pSJ6208 is an E. coli pUC derivative described in SEQ ID NO 31.

[0336] pSJ6321 is a pE194 derivative with an erythromycin marker gene. The plasmid also holds cryIIIA stabilizer sequence, DNA encoding the signal peptide of amyL fused to a protease followed by a downstream sequence of amyL (SEQ ID NO 32).

[0337] pMOL2743 is described in this example (SEQ ID NO 33)

[0338] pMOL2744 is described in this example (SEQ ID NO 34)

[0339] pMOL2746b is described in this example (SEQ ID NO 35)

Construction of Integration Vector Z::Z::streptavidin for B. licheniformis Expression

[0340] The synthetic gene (SEQ ID NO 29) encoding the Z::Z domaine was amplified by the primers SEQ ID NO 36 and SEQ ID NO 37:

TABLE-US-00001 SEQ ID NO 36: TCATTCTGCAGCAGCGGCGGATAACAAATTTAACAAAGAACAGCA- GAACGCGTTTTATGAAA SEQ ID NO 37: AACTAAGCGGCCGCTAGCGACTACACTTTAGGAGCTTGCGCGTCAT- TAAGCT

[0341] The PCR fragment was digested with PstI-EagI and the 368 bp fragment was purified and ligated into the E. coli pUC derivative plasmid pSJ6208 (SEQ ID NO 31) digested with PstI EagI giving a 3389 bp fragment. The ligation mixture was transformed into E. coli SJ2 (Diderichsen, B., Wedsted, U., Hedegaard, L., Jensen, B. R., Sjoholm, C. (1990). Cloning of aldB, which encodes acetolactate decarboxylase, an exoenzyme from Bacillus brevis). The plasmid holding the sub cloned Z::Z gene pMOL2743 (SEQ ID NO 33), was recovered using a QIAprep® Spin Miniprep kit (QIAGEN, Chatsworth, Calif.) according to the manufacturer's instructions.

[0342] The synthetic gene (SEQ ID NO 30) encoding streptavidin was digested with HindIII giving a fragment of 620 bp. The plasmid pMOL2743 was restricted with HindIII and treated with alcaline phosphatase to avoid relegation. The two fragments were ligated and transformed to the E. coli SJ2. The colonies were screened for presence of the streptavidin gene and clones were picked where the streptavidin gene is inserted in the right orientation giving rise to the plasmid pMOL2744 (SEQ ID NO 34). In this plasmid the genes encoding the Z::Z domaine and Streptavidin if translationally fused.

[0343] The hybrid gene encoding Z::Z::Streptavidin was transferred to an integration vector designed to allow integration of the amylase expression cassette into the chromosome of a B. licheniformis strain, that already contains an artificial tandem promoter integrated at the amyL locus, as described in example 6 of WO2005/123915. This was achieved by a ligation of three fragments. The first fragment is a PstI-BglII restriction digest of pMOL2744 giving rise to a 931 bp fragment. The second fragment is a BgIII-BamHI restriction digest of the plasmid pSJ6321 (SEQ ID NO 32) isolating a 4288 bp fragment. The third fragment is a BamHI-PstI digest of pSJ 6321 isolating a 1234 bp fragment. The three fragments were ligated and introduced by transformation into PL1801 giving rise to an integration vector pMOL2746b (SEQ ID NO 35).

[0344] This pMOL2746b plasmid is then re-transformed by either competence, electroporation or conjugation into a protease deficient Bacillus licheniformis and inserted by double homologoes integration at the amyL locus using an already inserted cryIIIA sequence and the amyl downstream sequence. The resulting Bacillus licheniformis strain has the artificial tandem promoter and cryIIIA sequence driving the Z::Z::Strepavidin expression from the amyL locus. The Bacillus licheniformis host is preferred to be protease deficient to allow expression of the Z::Z::Streptavidin hybrid protein. The following proteases can be deleted by standard techniques using double homologous recombination: mpr, aprE, nprE, vpr, bpr, epr, wprA and ispA.

[0345] The protease deficient Bacillus licheniformis host with the expression cassette encoding the Z::Z::Strepatavidin hybrid DAP protein is fermented in 100 ml shake flasks with CAL18-2 medium described above at 30° C., 300 rpm for 2 days. Samples are taken out day one and day two to evaluate the DAP expression on an SDS gel. The data show a protein band at the right size of 30 KDa.

[0346] The PCR fragment is digested with the restriction enzymes Rsa I and Hind III and the resulting 489 bp fragment is cloned into the 5327 pStrExp1 digested with the restriction enzymes Nru I and Hind III by DNA ligation and cloning into B. subtilis PL1801.

[0347] The DNA sequence of the open reading frame encoding the fusion protein is shown in SEQ ID NO: 38, and the protein sequence in SEQ ID NO: 39.

Example 4

Expression of the DAP Construct in Bacillus subtilis

[0348] Transformants of B. Subtilis PL1801 is grown in shake flasks as described in patent WO 2000/075344 and the fusion protein is recovered from the supernatant. The antibody binding and biotin binding properties of the fusion protein is confirmed as shown elsewhere herein.

Example 5

Purification of DAP

[0349] 5a. Chemically Synthesized DAP Purified by Size Exclusion Chromatography

[0350] The conjugation mixtures from example 1 were loaded on a size exclusion column in order to purify the DAP-molecules by removing reactants. The size exclusion chromatography was performed on a prepacked Superdex 200 16/60 column. 1 mL of DAP reaction solution was loaded on the column. The pump flow was 1.00 mL/min, the eluent was 150 mM NaCl, 50 mM Hepes pH 7.0 and fractions of 1 mL were collected. Fractions were pooled based on absorbance measurements at 280 nm in order to remove reactants.

[0351] The collected and pooled fractions were concentrated 10× using Amicon Ultracentrifuge tubes with a NWCO of 3000.

5b. Recombinant DAP by IgG-Sepharose Affinity Chromatography

[0352] Recombinant DAP molecules were purified from the fermentation broth by sterile filtration and subsequent column purification by IgG affinity chromatography.

[0353] The IgG-sepharose column was prepared by following the procedure supplied by the vendor:

[0354] 15 g CNBr-activated sepharose 4B from GE Healthcare was washed for 15 min with 3 L1 mM HCl. The washed medium was added to 25 mL 20 mg/mL IgG solution from DAKO NSA (X0903) and 50 mL 0.75 M NaCl, 0.15 M NaHCO₃ pH 8.3. The mixture was gently rotated for 95 min. at room temperature. Excess IgG was washed away with 75 mL 0.1 M NaHCO₃ pH 8.3 containing 0.5 M NaCl before the medium was incubated in 0.1 M Tris/HCl pH 8.0 for 2 hours. The medium was stored in 20% ethanol until use.

Generic Procedure for Purification of Recombinant DAP

[0355] The recombinant DAP molecules from examples 2 and 3 were purified by a generic affinity chromatographic method that takes advantage of the IgG binding domain shared by all the recombinant DAP constructs. The DAP molecules were purified from the sterile filtered fermentation broth.

[0356] The chromatography was performed on a XK26/20 column packed with approx. 30 mL IgG-sepharose. The fermentation broths were sterile filtered and between 65 mL and 80 mL was loaded depending on the volume of the filtered fermentation broth. The pump flow was 1.50 mL/min during sample load and 2 mL/min during wash and elution. Buffer A was 0.1 M NaH₂PO₄ pH 7.2, 0.15 M NaCl and buffer B: 0.1 M Citric acid pH 3.5. The column was washed with 15 column volumes buffer A following the sample load. The bound material was eluted with 5 column volumes buffer B before the column was regenerated with 10 column volumes buffer A. Fractions of 10 mL were collected. Eluate having an increase of absorbance at 280 nm was pooled and the pH was adjusted to 7.2 using 1 M Tris. The concentration of the DAP protein was calculated from the absorption at 280 nm and the theoretical absorption coefficients calculated from the primary sequence using GPMAW 8.0 (Trends in Biochemical Science, Vol 26, No. 11, November 2001, pp 687-689, "GPMAW--a software tool for analyzing proteins and peptides"; see also http://www.qpmaw.comi). The Mw of the purified proteins were determined by SDS-PAGE. The samples were stored at -18° C. before further analysis.

Example 6

Characterization of DAP Molecules with Regard to Binding Strength Measured on the Biacore Instrument

[0357] The commercialised surface plasmon resonance (SPR) technology for real time monitoring biomolecular binding event is used to measure the binding affinities for the prepared DAP candidates. The general principle of this technology is that a SPR sensor chip measures changes in refractive index, and the changes in refractive index correlate to changes in mass in the aqueous layer close to the sensor surface. When target molecules in solution bind to ligands, immobilised on the sensor surface, the mass increases, and when they dissociate from the ligands the mass decreases. This principle facilitates a continuous, real time monitoring of the association and dissociation of interacting molecules. The graphical presentation of the relationship provides quantitative information in real time on the binding specificity, active concentration of molecule in a sample, reaction kinetics and affinity.

[0358] In order to evaluate the binding affinities for both of the binding affinities present in the DAP either IgG or the capturing ligand had to be immobilized onto the sensor chip. For IgG rabbit anti-Mannanase was used and for the ligand the chip was coated with streptavidin and the ligand was then immobilized via biotin linked to the appropriate ligand.

[0359] In order to measure the binding to RR6 and acarbose the following compounds were prepared; biotin-linked acarbose and biotin-linked RR6.

Preparation of Biotin Linked Acarbose

[0360] Biotin (5 mg, 26 μmol) was dissolved in DMF (250 μL) in a 2 mL eppendorf tube, and to this EDC.HCl (5 mg, 26 μmol) was added. The mixture was stirred at RT for 30 min. Acarbose (16.1 mg, 25 μmol) was dissolved in DMF (250 μL) in a 2 mL eppendorf tube, and to this the activated biotin solution was added dropwise, while the reaction mixture was gently stirred. When all activated biotin solution was added, 100 μL DMF was used to wash the reaction container, and these 100 μL were also added to the acarbose solution. The reaction mixture was left stirring for 2 h at RT. Upon this, the DMF was removed by freeze-drying overnight at -5° C. The crude product was stored at -18° C., until used in the Biacore experiments.

Preparation of biotin linked Reactive Red 6

[0361] Biotin (5 mg, 26 μmol) was dissolved in DMF (250 μL) in a 2 mL eppendorf tube, and to this EDC.HCl (5 mg, 26 μmol) was added. The mixture was stirred at RT for 30 min. 1,4-Diaminobutane (25.1 μL, 25 μmol) was dissolved in DMF (250 μL) in a 2 mL eppendorf tube, and to this the activated biotin solution was added dropwise, while the reaction mixture was gently stirred. When all activated biotin solution was added, 100 μL DMF was used to wash the reaction container, and these 100 μL were also added to the diaminobutane solution. The reaction mixture was left stirring for 2 h at RT.

[0362] Reactive Red 6 (24.4 mg, 25 μmol) was dissolved in DMF (250 μL) in a 2 mL eppendorf tube, and to this the biotin-amide solution was added dropwise, while the reaction mixture was gently stirred. When all biotin-amide solution was added, 100 μl DMF was used to wash the reaction container and these 100 μL were also added to the RR6 solution.

[0363] The reaction mixture was left stirring overnight at RT. The DMF was removed by freeze-drying overnight at -5° C. The crude product was stored at -18° C., until used in the Biacore experiments.

Biacore Evaluation:

[0364] The DAP candidates were analysed for binding to the capturing ligand sensor chip and the target biomolecule sensor chip respectively. A Biacore 3000 instrument was used.

[0365] To study the interactions between the IgG-binding end of the DAP molecule and IgG on the one hand, and the interaction between the ligand-binding end and the ligand (biotin, acarbose, reactive red) on the other hand, IgG and ligand were immobilized onto the sensor surface of a sensor chip as described below.

[0366] Immobilisation occurred by direct covalent coupling to the surface (using the Amine Coupling Kit, BiaCore, GE Health Care) or via a capturing molecule as prescribed by the manufacturer (BiaCore, GE Health Care). The amount of coupled target was quantified and expressed in Refractive Units (RU).

[0367] Interactions were monitored by injecting samples (20 μl/min) over the prepared sensor surface of the chip. Unless stated otherwise, the binding was assessed in 10 mM sodium acetatbuffer pH 5.0 at room temperature.

Experiment 1

Chip: CM5

[0368] Immobilized target: rabbit anti-Mannanase (10 pg/ml) in 10 mM acetatbuffer pH 5.0.

[0369] Target RU: 1250 RU

[0370] Actual RU:

[0371] FC1: 1349

[0372] FC2: 1492

[0373] FC3: 1338

[0374] FC4: 1331

Samples:

[0375] FC1: Protein A, 1 pg/ml injected

[0376] FC2: Protein A--Avidin, 0.5 pg/ml injected

[0377] FC3: Protein A--Avidin, 0.5 pg/ml injected

[0378] FC4: Affibody (IgG)--Avidin, 0.6 pg/ml injected

Results:

TABLE-US-00002 [0379] ka kd KA KD Final RU Protein A Chi₂ = 0.06 4.35e5 3.4e-6 1.28e11 7.81e-12 140 Protein A- Avidin Chi₂ = 0.737 6.99e5 1.75e-7 3.99e12 2.5e-13 130 Chi₂ = 1.82 1.21e6 5.03e-5 2.41e10 4.15e-11 130 Affibody(IgG)- Avidin Chi₂ = 0.505 9.56e4 6.41e-8 1.49e12 6.7e-13 105

Experiment 2

Chip: CM5

[0380] Immobilized target: rabbit anti-Mannanase (10 μg/ml) in 10 mM acetatbuffer pH 5.0.

[0381] Target RU: 1250 RU

[0382] Actual RU:

[0383] FC2: 1697

[0384] FC3: 1665

Samples:

[0385] FC2: CBD-Z-Z-CBD, 10 μg/ml injected

[0386] FC3: CBD-Z-Z-CBD, 10 μg/ml injected

Results:

TABLE-US-00003 [0387] CBD-Z-Z- CBD ka kd KA KD Final RU Chi₂ = 2.3 1.46e5 2e-4 7.3e8 1.37e-9 200 Chi₂ = 3.78 1.23e5 2.08e-4 5.93e8 1.69e-9 200

Experiment 3

Chip: CM5

[0388] Immobilized target: rabbit anti-Mannanase (10 μg/ml) in 10 mM acetatbuffer pH 5.0.

[0389] Target RU: 1250 RU

[0390] Actual RU:

[0391] FC3: 1485

[0392] FC4: 1760

Samples:

[0393] FC3: AMG-Z, 10 pg/ml injected

[0394] FC4: AMG-ZZ, 10 pg/ml injected

Results:

TABLE-US-00004 [0395] ka kd KA KD Final RU AMG-Z Chi₂ = 6.76 2.69e6 1.08e-2 2.49e8 4.02e-9 5 AMG-ZZ Chi₂ = 2.97 3.46e5 4.1e-4 8.42e8 1.19e-9 150

Experiment 4

Chip: CM5

[0396] Immobilized target: rabbit anti-Mannanase (1 pg/ml) in 10 mM acetatbuffer pH 5.0.

[0397] Target RU: 625 RU

[0398] Actual RU:

[0399] FC1: 683

[0400] FC2: 731

[0401] FC3: 881

[0402] FC4: 716

Samples:

[0403] FC1: Protein A, 1 pg/ml injected

[0404] FC2: ZZ-CBD-CBD, 0.1 pg/ml injected

[0405] FC3: VhhRR6(R2)-Z, 1 pg/ml injected

[0406] FC4: CBD-Z-Z-CBD, 1 pg/ml injected

Results:

TABLE-US-00005 [0407] ka kd KA KD Final RU Protein A Chi₂ = 1.22 4.27e5 1.26e-4 3.38e9 2.95e-10 55 ZZ-CBD-CBD Chi₂ = 0.116 4.6e6 3.3e-4 1.39e10 7.18e-11 70 VhhRR6(R2)-Z Chi₂ = 2.35 3.2e5 1e-3 3.2e8 3.13e-9 70 CBD-Z-Z-CBD Chi₂ = 1.96 2.65e5 2.97e-4 8.94e8 1.12e-9 50

Experiment 5

Chip: SA

[0408] Immobilization: None. The Chip is pre-coated with Streptavidin.

[0409] Immobilisation of the ligand through Biotin-Streptavidin binding

[0410] FC1: Biotin-Acarbose, 10 μg/ml

[0411] FC2: Biotin-Acarbose, 10 μg/ml

[0412] FC3: Biotin-Reactive Red 6, 10 μg/ml

[0413] Binding of the DAP via the ligand-binding end of the molecule to the ligand.

[0414] FC1: AMG-Z-Z, 10 μg/ml

[0415] FC2: AMG-Z, 10 μg/ml

[0416] FC3: VhhRR6(R2)-Z, 10 μg/ml

Results:

TABLE-US-00006 [0417] ka kd KA KD Final RU AMG-Z-Z Chi₂ = 1.38 6.29e3 2.69e-3 2.34e6 4.27e-7 15 AMG-Z Chi₂ = 2.9 1.02e4 1.8e-3 5.64e6 1.77e-7 20 VhhRR6(R2)-Z Chi₂ = 3.24 1.72e4 3.99e-3 4.31e6 2.32e-7 15

Experiment 6

Chip: SA

[0418] Immobilization: None. The Chip is pre-coated with Streptavidin.

[0419] Immobilisation of the ligand through Biotin-Streptavidin binding

[0420] FC4: Biotin-Reactive Red 6, 10 μg/ml

[0421] Binding of the DAP via the ligand-binding end of the molecule to the ligand in the presence of IgG binding to the Z-domain of the DAP molecule.

[0422] FC4: VhhRR6(R2)-Z+IgG 9.3 μg/ml

Result:

TABLE-US-00007 [0423] VhhRR6(R2)- Z + IgG ka kd KA KD Final RU Chi₂ = 5.3 225 6.18e-3 3.65e4 2.74e-5 5

TABLE-US-00008 TABLE 1 IgG binding Ligand binding k_a k_d K_D k_a k_d K_D DAP (1/Ms) (1/s) (M) Ligand (1/Ms) (1/s) (M) Avidin-Protein A 1 × 10⁶ 3 × 10^-5 2 × 10^-11 Biotin^a -- -- -- Avidin-Affibody (IgG) 1 × 10³ 6 × 10^-8 7 × 10^-13 Biotin -- -- -- AMG-ZZ 4 × 10⁵ 4 × 10^-4 1 × 10^-9 Acarbose 6 × 10³ 3 × 10^-3 4 × 10^-7 AMG-Z 3 × 10⁶ 1 × 10^-2 4 × 10^-9 Acarbose 1 × 10⁴ 2 × 10^-3 2 × 10^-7 CBD-ZZ-CBD 2 × 10⁵ 2 × 10^-4 1 × 10^-9 Cellulose ZZ-CBD-CBD 5 × 10⁶ 3 × 10^-4 7 × 10^-11 Cellulose VhhRR6(R2)-Z 3 × 10⁵ 1 × 10^-3 3 × 10^-9 RR6^b 2 × 10⁴ 4 × 10^-3 2 × 10^-7 Protein A control 5 × 10⁵ 7 × 10^-5 2 × 10^-10 -- -- -- -- ^aBinding between biotin and avidin/streptavidin is not measured, since it is known to be very tight, and no dissociation can therefore be measured. ^bIf VhhRR6(R2)-Z is mixed with IgG before loading to the Biacore, the K_D is 10^-5M, however, the binding is broken completely as soon as the injection is stopped.

Example 7

Purification of Antibodies Using Dual Affinity Polypeptide Purification Technology

[0424] Below is a short description of a generally applicable procedure for immunoglobulin purification: [0425] 1. A disposable generic solid phase with a low molecular weight capturing ligand molecule. [0426] 2. The dual affinity polypeptide DAP (e.g. Avidin-Protein A) reacts with the IgG (target biomolecule) in the solution. The DAP molecules are immobilized on the solid phase (e.g. biotin-agarose) in a complex together with the target protein (IgG). [0427] 3. The column is washed to eliminate interfering non-product components. [0428] 4. The immunoglobulin is eluted from the column using an appropriate buffer at low pH. [0429] 5. The antibody containing fractions are collected and pH is neutralized. [0430] 6. The generic matrix containing immobilized dual affinity polypeptide may be discarded.

Materials and Methods:

[0431] All buffer ingredients were pro-analysis. Rabbit serum proteins and Rabbit IgG fraction, code X0903 were from DAKO NS, Denmark. Biotin Agarose was from Sigma-Aldrich; B6885-5mL.

[0432] The purification experiments were performed using a chromatography system comprising a fraction collector (Frac-100), a recorder (Rec-1), an optical unit and a control UV-1, all from GE Healthcare. For all experiments we used a BioRAd Econo-column ID 1.0 cm with a flow adaptor. The equilibration and dilution buffer was 0.1 M phosphate, 0.15 M NaCl, pH=7.2 (PBS). The elution buffer was 0.1 M citrate, pH=3.5, or alternatively 0.1 M glycine, pH=2.8.

[0433] The data processing was based on Abs 280 nm measurement using a Pharmacia Gene Quant II and the extinction coefficient for Rabbit IgG (1 g/L) of 1.35.

IgG Purification Analysis

[0434] All experiments were performed at room temperature.

Example 7a

Recovery of Rabbit IgG with free DAP [Protein A--Neutravidin]

[0435] The sorbent (Biotin Agarose, 5 mL) was allowed to settle in the column for 10 min. The column was packed at a flow of 1.46 mL/min. The column was equilibrated with 7.5 column volumes (CV) PBS. DAP (Protein A-Neutravidin) solution (4.5 mL from example 1b) was mixed with 100 μL Rabbit IgG stock solution (20 g/L) and incubated for 5 minutes on a magnetic stirrer. The reaction solution was loaded on the column and washed with 7.5 CV of PBS to remove excess of target protein. The IgG was recovered by elution with 3 CV of 0.1 M glycine buffer (pH 2.8). 5 mL fractions were collected and analyzed for IgG content by Abs 280. See Table 2 for results.

Example 7b

Recovery of Rabbit IgG with Immobilized DAP [Protein A--Neutravidin]

[0436] The gel material from example 7a with immobilized DAP [Protein A--Neutravidin] was regenerated with 7.5 CV PBS before analyzing the conventional affinity purification capabilities.

[0437] We loaded 2 mg IgG in 4.6 mL PBS solution on the column. After sample loading, the column was washed with 7.5 CV of PBS to remove excess of protein. Then the column was eluted with 3 CV of 0.1 M Glycine buffer (pH 2.8) to recover the IgG. 5 mL fractions were collected and analyzed for IgG content by Abs 280 and SDS-PAGE. See Table 2 for results.

TABLE-US-00009 TABLE 2 Flow through Recovered Example 1b - Free DAP 74% 26% Example 1b - Immobilized DAP 86% 14%

[0438] As seen in Table 2, we obtained approximately twice the binding capability (26% versus 14%) when DAP and IgG are reacted in solution prior to loading on the column compared to the conventional affinity chromatography applying immobilized DAP.

Example 7c

Purification of Rabbit IgG from Serum with free DAP [Protein A--Neutravidin]

[0439] We studied purification of IgG from rabbit serum to show the specificity of the DAP purification technology.

[0440] Approximately 1 mL of sorbent (Biotin Agarose) was allowed to settle in the column for 10 min. The column was packed at a flow of 1.46 mL/min. The column was equilibrated with 7.5 column volumes (CV) PBS. A 4.5 mL DAP (Protein A--Neutravidin) solution (from example 1b) were mixed with 115 μL rabbit serum and incubated for 5 minutes on a magnetic stirrer. The reaction solution was loaded on the column following a wash with 7.5 CV of PBS to remove excess of target protein. The IgG was recovered by elution with 3 CV of glycine buffer. 2.5 mL fractions were collected and analyzed for IgG content by Abs 280 and SDS-PAGE. See Table 3 for results.

Example 7d

Purification of Rabbit IgG from Serum with Immobilized DAP [Protein A--Neutravidin]

[0441] The gel from example 1c with immobilized DAP [Protein A--Neutravidin] was regenerated with 7.5 CV PBS before analyzing the conventional affinity purification capabilities

[0442] We loaded rabbit serum (115 μL rabbit serum in 4.5 mL PBS) solution on the column. After sample loading, the column was washed with 7.5 CV of PBS to remove excess of protein. Then the column was eluted with 3 CV of 0.1 M Glycine buffer (pH 2.8) to recover the target IgG. The gel was regenerated with 7.5 CV PBS before the next affinity purification cycle. 2.5 mL fractions were collected and analyzed for IgG content by Abs 280 and SDS-PAGE. See Table 3 for results.

TABLE-US-00010 TABLE 3 Recovered IgG (mg) from serum Example 1b - Free DAP 0.31 Example 1b - Immobilised DAP 0.18

[0443] As seen in Table 3, we obtained approximately twice the binding capability (0.31 mg versus 0.18 mg IgG), when DAP was reacted with rabbit serum in solution prior to contacting the biotin-agarose column compared to the conventional affinity chromatography applying immobilized DAP.

[0444] SDS-PAGE showed that only IgG molecules were obtained from serum, showing that the DAP purification technology is specific.

[0445] We repeated the analysis using the other DAP conjugate (Protein A-Avidin) and performed similar tests as above but included an analysis of the leakage of DAP from the column by repeated binding analysis to the immobilized DAP.

Example 7e

Recovery of Rabbit IgG with free DAP [Protein A--Avidin]

[0446] The sorbent (Biotin Agarose, 1 mL) was allowed to settle in the column for 10 min. The column was packed at a flow of 1.46 mL/min. The column was equilibrated with 7.5 column volumes (CV) PBS. 2 mL of DAP (Protein A--Avidin) solution (from example 3a) was mixed with 160 μL Rabbit IgG stock solution (20 g/L) and incubated for 5 minutes on a magnetic stirrer. The reaction solution (˜2 CV) was loaded on the column following a wash with 7.5 CV of PBS to remove excess of target protein. The IgG was recovered by elution with 3 CV of 0.1 M Citrate, pH=3.5. 2.5 mL fractions were collected and analyzed for IgG content by Abs 280. The results are shown in Table 4.

TABLE-US-00011 TABLE 4 Free DAP versus reuses of immobilised DAP technology (Protein A - Avidin conjugate) Rabbit IgG recovery 1. reuse of 2. reuse of 3. reuse of 4. reuse of Free immobilsed immobilsed immobilsed immobilsed DAP DAP DAP DAP DAP IgG Re- 1.20 0.30 0.40 0.40 0.30 covered (mg)

Example 7f

Recovery of Rabbit IgG with Immobilized DAP [Protein A--Avidin]

[0447] The gel from example 7e with immobilized DAP [Protein A--Avidin] was regenerated with 7.5 CV PBS before analyzing the conventional affinity purification capabilities The rabbit IgG stock solution (20 g/L) was diluted to a concentration of 1.5 mg/mL with PBS. In each runs 3.2 mg of IgG was loaded (in 2.16 mL) on the column. After sample loading (˜2 CV), the column was washed with 7.5 CV of PBS to remove excess of protein. Then the column was eluted with 3 CV of elution buffer (0.1 M Citrate, pH=3.5) to recover the target IgG. The gel was regenerated with 7.5 CV PBS before the next affinity purification cycle. 2.5 mL fractions were collected and analyzed for IgG content by Abs 280.

[0448] When DAP is reacted with 3.2 mg of IgG in solution prior to contacting with the Biotin-Agarose we recovered 1.2 mg of IgG compared to the 0.35 mg IgG which was recovered on average in four repeated cycles with immobilized DAP.

[0449] The above results thus illustrate the advantageous effect of using a DAP according to the invention compared to conventional chromatography.

Example 8

Recovery of IgG Using Dual Affinity Chromatography

[0450] The purified DAP molecules from examples 5a and 5b were evaluated in a generic purification assay.

[0451] The experiments were conducted at room temperature using an Akta explorer system. 0.6 mL solid phase material was packed at a flow rate of 1.2 mL/min in an empty glass column (6.6×100 mm) equipped with an adjustable flow adaptor (Omnifit). The column was packed in 0.1 M sodium phosphate, 0.15 M NaCl, pH=7.2 (PBS) and allowed to equilibrate with 10 column volumes PBS followed by 3 column volumes 0.1 M citrate, pH=3.5 and finally 10 column volumes PBS before use.

[0452] ZZ-CBD-CDB and CBD-ZZ-CBD were analyzed using a column packed with cellulose. 1.2 g Avicel (Merck product no. 1.02331) was suspended in 8 ml PBS in a test tube and the suspension was allowed to settle for 30 min. Subsequently the fine particles were decanted before the column was packed.

[0453] AMG-Z and AMG-ZZ were evaluated using a column packed with Acarbose-agarose. Approx. 0.6 mL of the Acarbose-agarose from Example 9 was transferred to the column and allowed to settle for 10 min before the column was packed.

[0454] VhhRR6(R2)-Z was analysed using a column packed with RR6-agarose. Approx. 0.6 mL of the Reactive Red-agarose from Example 9 was transferred to the column and allowed to settle for 10 min before the column was packed.

[0455] Avidin-Protein A, Avidin-Affibody and ZZ-Streptavidin were evaluated using a column packed with Biotin-agarose. Approx. 0.6 mL of Biotin-agarose (Sigma B6885) was transferred to the column and allowed to settle for 10 min before the column was packed.

[0456] The packed column was operated at a flow rate of 0.6 mL/min. Buffer A was 0.1 M sodium phosphate pH 7.2, 0.15 M NaCl and buffer B was 0.1 M Citric acid pH 3.5. The column was initially washed with 10 column volumes buffer A before 0.6 mL sample was injected. The column was washed with 7.5 column volumes buffer A and the bound target protein was eluted with 5 column volumes buffer B. The column was finally regenerated with 10 column volumes buffer A. Detection was at 280 nm. The data were evaluated by determining the height of the peak observed during elution.

[0457] Purified DAP (8 nmole) was mixed with IgG (code X0903, DAKO NS, 8 nmole) and water was added ad 660 μL. The reaction mixture was incubated on a magnetic stirrer for 10 minutes before it was injected onto the column. The solution of target protein was prepared as a 2 mg/mL IgG solution in water. The following sequence of injections was carried out in all experiments: Water; target protein (7.1 nmole); target protein and DAP reaction mixture; and finally 10 times subsequent injections of target protein (7.1 nmole).

[0458] The column employed for evaluating the Protein A--Avidin DAP molecule was subsequently used for assessing the effect of changing the load of target protein by varying the injection volume. Four injections were made: (0.6; 0.45; 0.3; 0.15) mL of the same IgG solution (12 μM). The results showed that the height of the peak observed during elution was almost constant whereas the height of peak observed in the flow through decreased markedly as the column load was lowered (Table 5). These results are in accordance with the nature of affinity chromatography and demonstrate that the applied approach of evaluating the data by using the height of the peak observed during elution is valid.

TABLE-US-00012 TABLE 5 Peak heights determined from injections of different volumes of IgG Injection volume Peak height of flow through Peak height eluate mL mAU mAU 0.6 154 126 0.45 116 124 0.3 61 120 0.15 14 109

[0459] The non-specific binding of target protein to the column was evaluated by injecting water and subsequently the target protein before the DAP molecule was introduced to the column material. The peak heights observed from injections of water and IgG were comparable in all the experiments performed. This demonstrates that the peak observed during elution is unaffected of potential non-specific binding of target protein to the column. Thus the peak observed during elution is a measure of the recovered amount of target protein from the non-covalently immobilized DAP.

[0460] The ability of the DAP molecules to recover the target protein was analyzed by comparing the chromatograms obtained from injection of water, target protein and the target protein/DAP reaction mixture. The results are shown in Table 6. Only two DAP molecules were unable to recover the target protein. 1) VhhRR6(R2)-Z did not recover IgG, which may be explained by results from the Biacore analysis showing that the binding between DAP and ligand is broken completely as soon as the injection is stopped (Table 1 footnote). This indicates that the DAP molecule is quickly released from the solid phase and thus not suitable for affinity chromatography. 2) The ZZ-streptavidin DAP did not recover IgG which is likely explained by a blocking of the biotin binding sites due to the reaction with endogenous biotin present in the fermentation broth. Thus this ZZ-streptavidin preparation is likely not to bind to the solid phase.

TABLE-US-00013 TABLE 6 Ability of DAP molecules to recover the target protein Binding and elution of DAP Column materiale target protein AMG-ZZ Acarbose-agarose + AMG-Z Acarbose-agarose + ZZ-CBD-CBD Cellulose + CBD-ZZ-CBD Cellulose + VhhRR6(R2)-Z Reactive red-agarose - ZZ-streptavidin Biotin-agarose - Affibody(IgG)-avidin Biotin-agarose + ProteinA-avidin Biotin-agarose +

[0461] The leakage of DAP from the column was assessed by 10 consecutive injections of the target protein following the initial injection of the DAP/target protein reaction mixture. The heights of the peaks observed during elution were determined and the relative responses were calculated relative to the first injection of IgG. The relative responses were plotted as a function of the injection number and the relative decrease in peak height was calculated by linear regression. The results from the different DAP--ligand combinations are shown in Table 7 together with the dissociation constants.

TABLE-US-00014 TABLE 7 Dissociation constants and relative leakage Rel dec- rease DAP K_D,t M K_D,s M K_D,t/K_D,s, %/inj r² AMG-ZZ 1 × 10^-9 4 × 10^-7 3 × 10^-3 -1.1 0.8 AMG-Z 4 × 10^-9 2 × 10^-7 2 × 10^-2 -1.7 1.0 ZZ-CBD-CBD^a .sup. 7 × 10^-11 10^-6 7 × 10^-5 -1.7 1.0 CBD-ZZ-CBD^a 1 × 10^-9 10^-6 1 × 10^-3 -1.7 0.9 Affibody(IgG)-avidin^b .sup. 7 × 10^-13 10^-15* 7 × 10² -0.2 .sup. 0.3^c Protein A-avidin^b .sup. 2 × 10^-11 10^-15* 2 × 10⁴ -0.7 0.9 ^aThe dissociation constant (K_D) of CBDs binding to cellulose is generally considered to be ≈10^-6M (Linder et al, Biotechnology and Bioengineering, Vol. 60, No. 5, Dec. 5, 1998). ^bThe dissociation constant (K_D) of avidin binding to biotin is well known to be 10^-15 M (Green, N. (1963). Biochem J, 89, 585-591). ^cThe correlation coefficient reflects that the calculated leakage is mainly determined by a single point. The relative leakage is -0.05% with r² = 0.0 if this point is removed.

[0462] The results in Table 7 show purification schemes of the same target molecule (IgG) using various compositions of DAP molecules. It is concluded that the most efficient DAP molecules in affinity chromatography are those with tighter binding to the ligand on the matrix, i.e. those having a relative K_D,t/K_D,s>10⁰=1.

[0463] Specifically, the strong binding towards the column provided by the avidin-biotin bond prevents leakage of the bound DAP molecules.

Example 9

Preparation of Functionalized Resins

Materials

[0464] Resin: Mini-Leak-Low (loading 2-5 mM, Kem-En-Tec). [0465] Ligands: 1,4-Diaminobutane ([110-60-1], Sigma-Aldrich, D13208), Reactive Red 6 (Cherry red #14, Grateful Dyes inc.), Acarbose ([56180-94-0] Sigma-Aldrich, A8980). [0466] Coupling buffer: 0.5M K₂HPO₄--pH 8.5 [0467] Washing buffer: 0.5M K₂HPO₄--pH 7.0 [0468] Blocking buffer 0.1M Ethanolamine in Milli-Q water

Preparation of an RR6-Agarose Resin

[0469] Resin (10 ml, suspended) was washed 2× with destilled water and the water removed by filtration. 1,4-Diaminobutane (2.0 mL) was dissolved in coupling buffer (20 mL) and the resin was added slowly with gentle shaking. The resin was left shaking overnight at RT, whereupon it was washed with coupling buffer and sucked dry.

[0470] Reactive Red 6 (15.9 g) was dissolved in coupling buffer (50 mL) and to this solution, the amino-functionalized resin was added slowly with shaking. Again the resin was left shaking overnight at RT. After washing with water and washing buffer, the resin was transferred to blocking buffer (20 mL) and shaken for 2 h. Finally the resin was washed in water until the filtrate was colorless, and the red resin was suspended in 30% ethanol in Milli-Q water.

Preparation of an Acarbose-Agarose Resin

[0471] Resin (10 ml, suspended) was washed 2× with destilled water and the water removed by filtration. Acarbose (500 mg) was dissolved in coupling buffer (20 mL) and the resin was added slowly with gentle shaking. The resin was left shaking overnight at RT, whereupon it was washed with water and washing buffer.

[0472] The resin was transferred to blocking buffer (20 mL) and shaken for 2 h. Finally the resin was washed in water, and the resulting resin was suspended in 30% ethanol in Milli-Q water.

Sequence CWU 1

391972DNAArtificial Sequencefusion protein coding sequence 1ggatccacca tgaaggcgat cctctctctc gctgccgcgc tcttgagcgc cgcgcccgcg 60ttctcgaccg cagtctgggg ccagtgcggt ggcatcggct tctccggcga caccacgtgc 120accgcttcca cctgcgtgaa ggtcaacgac tactactcgc agtgccagcc tggcgcgtcc 180gcacccacgt caaccgcctc cgcgcccggc ccgtccgcgt gccctttggt gaagcgtcag 240gtgcagttgc aggaatcggg tggaggactc gtgcaggcag gtggctcgct ccggttgtcg 300tgtgcagcct cgggcagggc gacatcggga catggccatt acggtatggg atggttccgc 360caggtgcctg gaaaggaacg agaattcgtc gcagccatcc ggtggtccgg caaagagacc 420tggtacaaag attcggtgaa aggacggttc accatctcca gggataacgc gaaaactact 480gtctacctcc agatgaactc gctcaagccc gaggatacgg cagtgtatta ctgtgccgca 540aggcctgtcc gagtggacga catctcgctc cccgtgggtt tcgattactg gggacagggt 600acgcaggtga cggtctcctc cgataacaaa ttcaacaagg aacagcagaa cgcgttctac 660gagatcttgc acctccccaa cctcaacgag gaacagagga acggtttcat tcagtcgctc 720aaggacgacc cctcccagtc cgccaacctc ttggcagaag ccaagaagtt gaacgatgca 780caggcaccga aagacaacaa gttcaacaaa gagcagcaga acgccttcta tgagatcttg 840catctcccga acttgaacga ggagcagcgg aacggcttca tccagtcctt gaaagatgat 900ccctcgcagt cggccaacct cctcgcagaa gcgaagaagc tcaacgacgc gcaggcacct 960aagtgactcg ag 9722318PRTArtificial Sequencefusion protein 2Met Lys Ala Ile Leu Ser Leu Ala Ala Ala Leu Leu Ser Ala Ala Pro1 5 10 15Ala Phe Ser Thr Ala Val Trp Gly Gln Cys Gly Gly Ile Gly Phe Ser 20 25 30Gly Asp Thr Thr Cys Thr Ala Ser Thr Cys Val Lys Val Asn Asp Tyr 35 40 45Tyr Ser Gln Cys Gln Pro Gly Ala Ser Ala Pro Thr Ser Thr Ala Ser 50 55 60Ala Pro Gly Pro Ser Ala Cys Pro Leu Val Lys Arg Gln Val Gln Leu65 70 75 80Gln Glu Ser Gly Gly Gly Leu Val Gln Ala Gly Gly Ser Leu Arg Leu 85 90 95Ser Cys Ala Ala Ser Gly Arg Ala Thr Ser Gly His Gly His Tyr Gly 100 105 110Met Gly Trp Phe Arg Gln Val Pro Gly Lys Glu Arg Glu Phe Val Ala 115 120 125Ala Ile Arg Trp Ser Gly Lys Glu Thr Trp Tyr Lys Asp Ser Val Lys 130 135 140Gly Arg Phe Thr Ile Ser Arg Asp Asn Ala Lys Thr Thr Val Tyr Leu145 150 155 160Gln Met Asn Ser Leu Lys Pro Glu Asp Thr Ala Val Tyr Tyr Cys Ala 165 170 175Ala Arg Pro Val Arg Val Asp Asp Ile Ser Leu Pro Val Gly Phe Asp 180 185 190Tyr Trp Gly Gln Gly Thr Gln Val Thr Val Ser Ser Asp Asn Lys Phe 195 200 205Asn Lys Glu Gln Gln Asn Ala Phe Tyr Glu Ile Leu His Leu Pro Asn 210 215 220Leu Asn Glu Glu Gln Arg Asn Gly Phe Ile Gln Ser Leu Lys Asp Asp225 230 235 240Pro Ser Gln Ser Ala Asn Leu Leu Ala Glu Ala Lys Lys Leu Asn Asp 245 250 255Ala Gln Ala Pro Lys Asp Asn Lys Phe Asn Lys Glu Gln Gln Asn Ala 260 265 270Phe Tyr Glu Ile Leu His Leu Pro Asn Leu Asn Glu Glu Gln Arg Asn 275 280 285Gly Phe Ile Gln Ser Leu Lys Asp Asp Pro Ser Gln Ser Ala Asn Leu 290 295 300Leu Ala Glu Ala Lys Lys Leu Asn Asp Ala Gln Ala Pro Lys305 310 3153261PRTArtificial Sequencefusion protein 3Met Lys Ala Ile Leu Ser Leu Ala Ala Ala Leu Leu Ser Ala Ala Pro1 5 10 15Ala Phe Ser Thr Ala Val Trp Gly Gln Cys Gly Gly Ile Gly Phe Ser 20 25 30Gly Asp Thr Thr Cys Thr Ala Ser Thr Cys Val Lys Val Asn Asp Tyr 35 40 45Tyr Ser Gln Cys Gln Pro Gly Ala Ser Ala Pro Thr Ser Thr Ala Ser 50 55 60Ala Pro Gly Pro Ser Ala Cys Pro Leu Val Lys Arg Gln Val Gln Leu65 70 75 80Gln Glu Ser Gly Gly Gly Leu Val Gln Ala Gly Gly Ser Leu Arg Leu 85 90 95Ser Cys Ala Ala Ser Gly Arg Ala Thr Ser Gly His Gly His Tyr Gly 100 105 110Met Gly Trp Phe Arg Gln Val Pro Gly Lys Glu Arg Glu Phe Val Ala 115 120 125Ala Ile Arg Trp Ser Gly Lys Glu Thr Trp Tyr Lys Asp Ser Val Lys 130 135 140Gly Arg Phe Thr Ile Ser Arg Asp Asn Ala Lys Thr Thr Val Tyr Leu145 150 155 160Gln Met Asn Ser Leu Lys Pro Glu Asp Thr Ala Val Tyr Tyr Cys Ala 165 170 175Ala Arg Pro Val Arg Val Asp Asp Ile Ser Leu Pro Val Gly Phe Asp 180 185 190Tyr Trp Gly Gln Gly Thr Gln Val Thr Val Ser Ser Asp Asn Lys Phe 195 200 205Asn Lys Glu Gln Gln Asn Ala Phe Tyr Glu Ile Leu His Leu Pro Asn 210 215 220Leu Asn Glu Glu Gln Arg Asn Gly Phe Ile Gln Ser Leu Lys Asp Asp225 230 235 240Pro Ser Gln Ser Ala Asn Leu Leu Ala Glu Ala Lys Lys Leu Asn Asp 245 250 255Ala Gln Ala Pro Lys 2604469DNAArtificial Sequencefusion protein coding sequence 4cacctcgtgg ccgagtatcg tggctactgg cggcaccact acgacggcta cccccactgg 60atcaggcagc gtgacctcga ccagcaagac caccgcgact gctagcaaga ccagcaccga 120taacaaattc aacaaggaac agcagaacgc gttctacgag atcttgcacc tccccaacct 180caacgaggaa cagaggaacg gtttcattca gtcgctcaag gacgacccct cccagtccgc 240caacctcttg gcagaagcca agaagttgaa cgatgcacag gcaccgaaag acaacaagtt 300caacaaagag cagcagaacg ccttctatga gatcttgcat ctcccgaact tgaacgagga 360gcagcggaac ggcttcatcc agtccttgaa agatgatccc tcgcagtcgg ccaacctcct 420cgcagaagcg aagaagctca acgacgcgca ggcacctaag tgactcgag 469577DNAArtificial Sequenceadaptor sequence 5cgcgcttgga aatcacattt gccaaccctg tgcagacgag gccgctcagg gcgagtagag 60atcggaacga catggtg 77677DNAArtificial Sequenceadaptor sequence 6gatccaccat gtcgttccga tctctactcg ccctgagcgg cctcgtctgc acagggttgg 60caaatgtgat ttccaag 777639PRTArtificial Sequencefusion protein 7Met Ser Phe Arg Ser Leu Leu Ala Leu Ser Gly Leu Val Cys Thr Gly1 5 10 15Leu Ala Asn Val Ile Ser Lys Arg Ala Thr Leu Asp Ser Trp Leu Ser 20 25 30Asn Glu Ala Thr Val Ala Arg Thr Ala Ile Leu Asn Asn Ile Gly Ala 35 40 45Asp Gly Ala Trp Val Ser Gly Ala Asp Ser Gly Ile Val Val Ala Ser 50 55 60Pro Ser Thr Asp Asn Pro Asp Phe Tyr Thr Trp Thr Arg Asp Ser Gly65 70 75 80Leu Val Leu Lys Thr Leu Val Asp Leu Phe Arg Asn Gly Asp Thr Ser 85 90 95Leu Leu Ser Thr Ile Glu Asn Tyr Ile Ser Ala Gln Ala Ile Val Gln 100 105 110Gly Ile Ser Asn Pro Ser Gly Asp Leu Ser Ser Gly Ala Gly Leu Gly 115 120 125Glu Pro Lys Phe Asn Val Asp Glu Thr Ala Tyr Thr Gly Ser Trp Gly 130 135 140Arg Pro Gln Arg Asp Gly Pro Ala Leu Arg Ala Thr Ala Met Ile Gly145 150 155 160Phe Gly Gln Trp Leu Leu Asp Asn Gly Tyr Thr Ser Thr Ala Thr Asp 165 170 175Ile Val Trp Pro Leu Val Arg Asn Asp Leu Ser Tyr Val Ala Gln Tyr 180 185 190Trp Asn Gln Thr Gly Tyr Asp Leu Trp Glu Glu Val Asn Gly Ser Ser 195 200 205Phe Phe Thr Ile Ala Val Gln His Arg Ala Leu Val Glu Gly Ser Ala 210 215 220Phe Ala Thr Ala Val Gly Ser Ser Cys Ser Trp Cys Asp Ser Gln Ala225 230 235 240Pro Glu Ile Leu Cys Tyr Leu Gln Ser Phe Trp Thr Gly Ser Phe Ile 245 250 255Leu Ala Asn Phe Asp Ser Ser Arg Ser Gly Lys Asp Ala Asn Thr Leu 260 265 270Leu Gly Ser Ile His Thr Phe Asp Pro Glu Ala Ala Cys Asp Asp Ser 275 280 285Thr Phe Gln Pro Cys Ser Pro Arg Ala Leu Ala Asn His Lys Glu Val 290 295 300Val Asp Ser Phe Arg Ser Ile Tyr Thr Leu Asn Asp Gly Leu Ser Asp305 310 315 320Ser Glu Ala Val Ala Val Gly Arg Tyr Pro Glu Asp Thr Tyr Tyr Asn 325 330 335Gly Asn Pro Trp Phe Leu Cys Thr Leu Ala Ala Ala Glu Gln Leu Tyr 340 345 350Asp Ala Leu Tyr Gln Trp Asp Lys Gln Gly Ser Leu Glu Val Thr Asp 355 360 365Val Ser Leu Asp Phe Phe Lys Ala Leu Tyr Ser Asp Ala Ala Thr Gly 370 375 380Thr Tyr Ser Ser Ser Ser Ser Thr Tyr Ser Ser Ile Val Asp Ala Val385 390 395 400Lys Thr Phe Ala Asp Gly Phe Val Ser Ile Val Glu Thr His Ala Ala 405 410 415Ser Asn Gly Ser Met Ser Glu Gln Tyr Asp Lys Ser Asp Gly Glu Gln 420 425 430Leu Ser Ala Arg Asp Leu Thr Trp Ser Tyr Ala Ala Leu Leu Thr Ala 435 440 445Asn Asn Arg Arg Asn Ser Val Val Pro Ala Ser Trp Gly Glu Thr Ser 450 455 460Ala Ser Ser Val Pro Gly Thr Cys Ala Ala Thr Ser Ala Ile Gly Thr465 470 475 480Tyr Ser Ser Val Thr Val Thr Ser Trp Pro Ser Ile Val Ala Thr Gly 485 490 495Gly Thr Thr Thr Thr Ala Thr Pro Thr Gly Ser Gly Ser Val Thr Ser 500 505 510Thr Ser Lys Thr Thr Ala Thr Ala Ser Lys Thr Ser Thr Asp Asn Lys 515 520 525Phe Asn Lys Glu Gln Gln Asn Ala Phe Tyr Glu Ile Leu His Leu Pro 530 535 540Asn Leu Asn Glu Glu Gln Arg Asn Gly Phe Ile Gln Ser Leu Lys Asp545 550 555 560Asp Pro Ser Gln Ser Ala Asn Leu Leu Ala Glu Ala Lys Lys Leu Asn 565 570 575Asp Ala Gln Ala Pro Lys Asp Asn Lys Phe Asn Lys Glu Gln Gln Asn 580 585 590Ala Phe Tyr Glu Ile Leu His Leu Pro Asn Leu Asn Glu Glu Gln Arg 595 600 605Asn Gly Phe Ile Gln Ser Leu Lys Asp Asp Pro Ser Gln Ser Ala Asn 610 615 620Leu Leu Ala Glu Ala Lys Lys Leu Asn Asp Ala Gln Ala Pro Lys625 630 6358583PRTArtificial Sequencefusion protein 8Met Ser Phe Arg Ser Leu Leu Ala Leu Ser Gly Leu Val Cys Thr Gly1 5 10 15Leu Ala Asn Val Ile Ser Lys Arg Ala Thr Leu Asp Ser Trp Leu Ser 20 25 30Asn Glu Ala Thr Val Ala Arg Thr Ala Ile Leu Asn Asn Ile Gly Ala 35 40 45Asp Gly Ala Trp Val Ser Gly Ala Asp Ser Gly Ile Val Val Ala Ser 50 55 60Pro Ser Thr Asp Asn Pro Asp Tyr Phe Tyr Thr Trp Thr Arg Asp Ser65 70 75 80Gly Leu Val Leu Lys Thr Leu Val Asp Leu Phe Arg Asn Gly Asp Thr 85 90 95Ser Leu Leu Ser Thr Ile Glu Asn Tyr Ile Ser Ala Gln Ala Ile Val 100 105 110Gln Gly Ile Ser Asn Pro Ser Gly Asp Leu Ser Ser Gly Ala Gly Leu 115 120 125Gly Glu Pro Lys Phe Asn Val Asp Glu Thr Ala Tyr Thr Gly Ser Trp 130 135 140Gly Arg Pro Gln Arg Asp Gly Pro Ala Leu Arg Ala Thr Ala Met Ile145 150 155 160Gly Phe Gly Gln Trp Leu Leu Asp Asn Gly Tyr Thr Ser Thr Ala Thr 165 170 175Asp Ile Val Trp Pro Leu Val Arg Asn Asp Leu Ser Tyr Val Ala Gln 180 185 190Tyr Trp Asn Gln Thr Gly Tyr Asp Leu Trp Glu Glu Val Asn Gly Ser 195 200 205Ser Phe Phe Thr Ile Ala Val Gln His Arg Ala Leu Val Glu Gly Ser 210 215 220Ala Phe Ala Thr Ala Val Gly Ser Ser Cys Ser Trp Cys Asp Ser Gln225 230 235 240Ala Pro Glu Ile Leu Cys Tyr Leu Gln Ser Phe Trp Thr Gly Ser Phe 245 250 255Ile Leu Ala Asn Phe Asp Ser Ser Arg Ser Gly Lys Asp Ala Asn Thr 260 265 270Leu Leu Gly Ser Ile His Thr Phe Asp Pro Glu Ala Ala Cys Asp Asp 275 280 285Ser Thr Phe Gln Pro Cys Ser Pro Arg Ala Leu Ala Asn His Lys Glu 290 295 300Val Val Asp Ser Phe Arg Ser Ile Tyr Thr Leu Asn Asp Gly Leu Ser305 310 315 320Asp Ser Glu Ala Val Ala Val Gly Arg Tyr Pro Glu Asp Thr Tyr Tyr 325 330 335Asn Gly Asn Pro Trp Phe Leu Cys Thr Leu Ala Ala Ala Glu Gln Leu 340 345 350Tyr Asp Ala Leu Tyr Gln Trp Asp Lys Gln Gly Ser Leu Glu Val Thr 355 360 365Asp Val Ser Leu Asp Phe Phe Lys Ala Leu Tyr Ser Asp Ala Ala Thr 370 375 380Gly Thr Tyr Ser Ser Ser Ser Ser Thr Tyr Ser Ser Ile Val Asp Ala385 390 395 400Val Lys Thr Phe Ala Asp Gly Phe Val Ser Ile Val Glu Thr His Ala 405 410 415Ala Ser Asn Gly Ser Met Ser Glu Gln Tyr Asp Lys Ser Asp Gly Glu 420 425 430Gln Leu Ser Ala Arg Asp Leu Thr Trp Ser Tyr Ala Ala Leu Leu Thr 435 440 445Ala Asn Asn Arg Arg Asn Ser Val Val Pro Ala Ser Trp Gly Glu Thr 450 455 460Ser Ala Ser Ser Val Pro Gly Thr Cys Ala Ala Thr Ser Ala Ile Gly465 470 475 480Thr Tyr Ser Ser Val Thr Val Thr Ser Trp Pro Ser Ile Val Ala Thr 485 490 495Gly Gly Thr Thr Thr Thr Ala Thr Pro Thr Gly Ser Gly Ser Val Thr 500 505 510Ser Thr Ser Lys Thr Thr Ala Thr Ala Ser Lys Thr Ser Thr Asp Asn 515 520 525Lys Phe Asn Lys Glu Gln Gln Asn Ala Phe Tyr Glu Ile Leu His Leu 530 535 540Pro Asn Leu Asn Glu Glu Gln Arg Asn Gly Phe Ile Gln Ser Leu Lys545 550 555 560Asp Asp Pro Ser Gln Ser Ala Asn Leu Leu Ala Glu Ala Lys Lys Leu 565 570 575Asn Asp Ala Gln Ala Pro Lys 5809259PRTArtificial Sequencefusion protein 9Met Lys Ala Ile Leu Ser Leu Ala Ala Ala Leu Leu Ser Ala Ala Pro1 5 10 15Ala Phe Ser Thr Ala Val Trp Gly Gln Cys Gly Gly Ile Gly Phe Ser 20 25 30Gly Asp Thr Thr Cys Thr Ala Ser Thr Cys Val Lys Val Asn Asp Tyr 35 40 45Tyr Ser Gln Cys Gln Pro Gly Ala Ser Ala Pro Thr Ser Thr Ala Ser 50 55 60Ala Pro Gly Pro Ser Ala Cys Pro Gly Ser Asp Asn Lys Phe Asn Lys65 70 75 80Glu Gln Gln Asn Ala Phe Tyr Glu Ile Leu His Leu Pro Asn Leu Asn 85 90 95Glu Glu Gln Arg Asn Gly Phe Ile Gln Ser Leu Lys Asp Asp Pro Ser 100 105 110Gln Ser Ala Asn Leu Leu Ala Glu Ala Lys Lys Leu Asn Asp Ala Gln 115 120 125Ala Pro Lys Asp Asn Lys Phe Asn Lys Glu Gln Gln Asn Ala Phe Tyr 130 135 140Glu Ile Leu His Leu Pro Asn Leu Asn Glu Glu Gln Arg Asn Gly Phe145 150 155 160Ile Gln Ser Leu Lys Asp Asp Pro Ser Gln Ser Ala Asn Leu Leu Ala 165 170 175Glu Ala Lys Lys Leu Asn Asp Ala Gln Ala Pro Lys Ser Ser Ser Thr 180 185 190Ser Ser Pro Val Asn Gln Pro Thr Ser Thr Ser Thr Thr Ser Thr Ser 195 200 205Thr Thr Ser Ser Pro Pro Val Gln Pro Thr Thr Pro Ser Gly Cys Thr 210 215 220Ala Glu Arg Trp Ala Gln Cys Gly Gly Asn Gly Trp Ser Gly Cys Thr225 230 235 240Thr Cys Val Ala Gly Ser Thr Cys Thr Lys Ile Asn Asp Trp Tyr His 245 250 255Gln Cys Leu 1020DNAArtificial SequencePrimer 10gcaagggatg ccatgcttgg 201138DNAArtificial SequencePrimer 11cttgttgaat ttgttatccg agccagggca cgcggacg 381238DNAArtificial SequencePrimer 12cgtccgcgtg ccctggctcg gataacaaat tcaacaag 381342DNAArtificial SequencePrimer 13ggagagctgg tgctgctgga cttaggtgcc tgcgcgtcgt tg 421442DNAArtificial SequencePrimer 14caacgacgcg caggcaccta agtccagcag

caccagctct cc 421519DNAArtificial SequencePrimer 15catataacca attgccctc 1916372DNAArtificial Sequencefusion protein coding sequence 16atgaaggcga tcctctctct cgctgccgcg ctcttgagcg ccgcgcccgc gttctcgacc 60gcagtctggg gccagtgcgg tggcatcggc ttctccggcg acaccacgtg caccgcttcc 120acctgcgtga aggtcaacga ctactactcg cagtgccagc ctggcgcgtc cgcacccacg 180tcaaccgcct ccgcgcccgg cccgtccgcg tgccctggct cgcagtcgag cccgccagtc 240cagcctacga ctcccagcgg ctgcactgct gagaggtggg ctcagtgcgg cggcaatggc 300tggagcggct gcaccacctg cgtcgctggc agcacttgca cgaagattaa tgactggtac 360catcagtgcc tg 37217124PRTArtificial Sequencefusion protein 17Met Lys Ala Ile Leu Ser Leu Ala Ala Ala Leu Leu Ser Ala Ala Pro1 5 10 15Ala Phe Ser Thr Ala Val Trp Gly Gln Cys Gly Gly Ile Gly Phe Ser 20 25 30Gly Asp Thr Thr Cys Thr Ala Ser Thr Cys Val Lys Val Asn Asp Tyr 35 40 45Tyr Ser Gln Cys Gln Pro Gly Ala Ser Ala Pro Thr Ser Thr Ala Ser 50 55 60Ala Pro Gly Pro Ser Ala Cys Pro Gly Ser Gln Ser Ser Pro Pro Val65 70 75 80Gln Pro Thr Thr Pro Ser Gly Cys Thr Ala Glu Arg Trp Ala Gln Cys 85 90 95Gly Gly Asn Gly Trp Ser Gly Cys Thr Thr Cys Val Ala Gly Ser Thr 100 105 110Cys Thr Lys Ile Asn Asp Trp Tyr His Gln Cys Leu 115 12018294PRTArtificial Sequencefusion protein 18Met Lys Ala Ile Leu Ser Leu Ala Ala Ala Leu Leu Ser Ala Ala Pro1 5 10 15Ala Phe Ser Thr Ala Val Trp Gly Gln Cys Gly Gly Ile Gly Phe Ser 20 25 30Gly Asp Thr Thr Cys Thr Ala Ser Thr Cys Val Lys Val Asn Asp Tyr 35 40 45Tyr Ser Gln Cys Gln Pro Gly Ala Ser Ala Pro Thr Ser Thr Ala Ser 50 55 60Ala Pro Gly Pro Ser Ala Cys Pro Leu Val Lys Arg Asp Asn Lys Phe65 70 75 80Asn Lys Glu Gln Gln Asn Ala Phe Tyr Glu Ile Leu His Leu Pro Asn 85 90 95Leu Asn Glu Glu Gln Arg Asn Gly Phe Ile Gln Ser Leu Lys Asp Asp 100 105 110Pro Ser Gln Ser Ala Asn Leu Leu Ala Glu Ala Lys Lys Leu Asn Asp 115 120 125Ala Gln Ala Pro Lys Asp Asn Lys Phe Asn Lys Glu Gln Gln Asn Ala 130 135 140Phe Tyr Glu Ile Leu His Leu Pro Asn Leu Asn Glu Glu Gln Arg Asn145 150 155 160Gly Phe Ile Gln Ser Leu Lys Asp Asp Pro Ser Gln Ser Ala Asn Leu 165 170 175Leu Ala Glu Ala Lys Lys Leu Asn Asp Ala Gln Ala Pro Lys Ala Val 180 185 190Trp Gly Gln Cys Gly Gly Ile Gly Phe Ser Gly Asp Thr Thr Cys Thr 195 200 205Ala Ser Thr Cys Val Lys Val Asn Asp Tyr Tyr Ser Gln Cys Gln Pro 210 215 220Gly Ala Ser Ala Pro Thr Ser Thr Ala Ser Ala Pro Gly Pro Ser Ala225 230 235 240Cys Pro Gly Ser Gln Ser Ser Pro Pro Val Gln Pro Thr Thr Pro Ser 245 250 255Gly Cys Thr Ala Glu Arg Trp Ala Gln Cys Gly Gly Asn Gly Trp Ser 260 265 270Gly Cys Thr Thr Cys Val Ala Gly Ser Thr Cys Thr Lys Ile Asn Asp 275 280 285Trp Tyr His Gln Cys Leu 2901938DNAArtificial SequencePrimer 19cttgttgaat ttgttatcac gcttcaccaa agggcacg 382038DNAArtificial SequencePrimer 20cgtgcccttt ggtgaagcgt gataacaaat tcaacaag 382142DNAArtificial SequencePrimer 21ccgcactggc cccagactgc cttaggtgcc tgcgcgtcgt tg 422242DNAArtificial SequencePrimer 22caacgacgcg caggcaccta aggcagtctg gggccagtgc gg 4223242PRTArtificial Sequencefusion protein 23Gln Val Gln Leu Gln Glu Ser Gly Gly Gly Leu Val Gln Ala Gly Gly1 5 10 15Ser Leu Arg Leu Ser Cys Ala Ala Ser Gly Arg Ala Thr Ser Gly His 20 25 30Gly His Tyr Gly Met Gly Trp Phe Arg Gln Val Pro Gly Lys Glu Arg 35 40 45Glu Phe Val Ala Ala Ile Arg Trp Ser Gly Lys Glu Thr Trp Tyr Lys 50 55 60Asp Ser Val Lys Gly Arg Phe Thr Ile Ser Arg Asp Asn Ala Lys Thr65 70 75 80Thr Val Tyr Leu Gln Met Asn Ser Leu Lys Pro Glu Asp Thr Ala Val 85 90 95Tyr Tyr Cys Ala Ala Arg Pro Val Arg Val Asp Asp Ile Ser Leu Pro 100 105 110Val Gly Phe Asp Tyr Trp Gly Gln Gly Thr Gln Val Thr Val Ser Ser 115 120 125Asp Asn Lys Phe Asn Lys Glu Gln Gln Asn Ala Phe Tyr Glu Ile Leu 130 135 140His Leu Pro Asn Leu Asn Glu Glu Gln Arg Asn Gly Phe Ile Gln Ser145 150 155 160Leu Lys Asp Asp Pro Ser Gln Ser Ala Asn Leu Leu Ala Glu Ala Lys 165 170 175Lys Leu Asn Asp Ala Gln Ala Pro Lys Asp Asn Lys Phe Asn Lys Glu 180 185 190Gln Gln Asn Ala Phe Tyr Glu Ile Leu His Leu Pro Asn Leu Asn Glu 195 200 205Glu Gln Arg Asn Gly Phe Ile Gln Ser Leu Lys Asp Asp Pro Ser Gln 210 215 220Ser Ala Asn Leu Leu Ala Glu Ala Lys Lys Leu Asn Asp Ala Gln Ala225 230 235 240Pro Lys24615PRTArtificial Sequencefusion protein 24Ala Thr Leu Asp Ser Trp Leu Ser Asn Glu Ala Thr Val Ala Arg Thr1 5 10 15Ala Ile Leu Asn Asn Ile Gly Ala Asp Gly Ala Trp Val Ser Gly Ala 20 25 30Asp Ser Gly Ile Val Val Ala Ser Pro Ser Thr Asp Asn Pro Asp Phe 35 40 45Tyr Thr Trp Thr Arg Asp Ser Gly Leu Val Leu Lys Thr Leu Val Asp 50 55 60Leu Phe Arg Asn Gly Asp Thr Ser Leu Leu Ser Thr Ile Glu Asn Tyr65 70 75 80Ile Ser Ala Gln Ala Ile Val Gln Gly Ile Ser Asn Pro Ser Gly Asp 85 90 95Leu Ser Ser Gly Ala Gly Leu Gly Glu Pro Lys Phe Asn Val Asp Glu 100 105 110Thr Ala Tyr Thr Gly Ser Trp Gly Arg Pro Gln Arg Asp Gly Pro Ala 115 120 125Leu Arg Ala Thr Ala Met Ile Gly Phe Gly Gln Trp Leu Leu Asp Asn 130 135 140Gly Tyr Thr Ser Thr Ala Thr Asp Ile Val Trp Pro Leu Val Arg Asn145 150 155 160Asp Leu Ser Tyr Val Ala Gln Tyr Trp Asn Gln Thr Gly Tyr Asp Leu 165 170 175Trp Glu Glu Val Asn Gly Ser Ser Phe Phe Thr Ile Ala Val Gln His 180 185 190Arg Ala Leu Val Glu Gly Ser Ala Phe Ala Thr Ala Val Gly Ser Ser 195 200 205Cys Ser Trp Cys Asp Ser Gln Ala Pro Glu Ile Leu Cys Tyr Leu Gln 210 215 220Ser Phe Trp Thr Gly Ser Phe Ile Leu Ala Asn Phe Asp Ser Ser Arg225 230 235 240Ser Gly Lys Asp Ala Asn Thr Leu Leu Gly Ser Ile His Thr Phe Asp 245 250 255Pro Glu Ala Ala Cys Asp Asp Ser Thr Phe Gln Pro Cys Ser Pro Arg 260 265 270Ala Leu Ala Asn His Lys Glu Val Val Asp Ser Phe Arg Ser Ile Tyr 275 280 285Thr Leu Asn Asp Gly Leu Ser Asp Ser Glu Ala Val Ala Val Gly Arg 290 295 300Tyr Pro Glu Asp Thr Tyr Tyr Asn Gly Asn Pro Trp Phe Leu Cys Thr305 310 315 320Leu Ala Ala Ala Glu Gln Leu Tyr Asp Ala Leu Tyr Gln Trp Asp Lys 325 330 335Gln Gly Ser Leu Glu Val Thr Asp Val Ser Leu Asp Phe Phe Lys Ala 340 345 350Leu Tyr Ser Asp Ala Ala Thr Gly Thr Tyr Ser Ser Ser Ser Ser Thr 355 360 365Tyr Ser Ser Ile Val Asp Ala Val Lys Thr Phe Ala Asp Gly Phe Val 370 375 380Ser Ile Val Glu Thr His Ala Ala Ser Asn Gly Ser Met Ser Glu Gln385 390 395 400Tyr Asp Lys Ser Asp Gly Glu Gln Leu Ser Ala Arg Asp Leu Thr Trp 405 410 415Ser Tyr Ala Ala Leu Leu Thr Ala Asn Asn Arg Arg Asn Ser Val Val 420 425 430Pro Ala Ser Trp Gly Glu Thr Ser Ala Ser Ser Val Pro Gly Thr Cys 435 440 445Ala Ala Thr Ser Ala Ile Gly Thr Tyr Ser Ser Val Thr Val Thr Ser 450 455 460Trp Pro Ser Ile Val Ala Thr Gly Gly Thr Thr Thr Thr Ala Thr Pro465 470 475 480Thr Gly Ser Gly Ser Val Thr Ser Thr Ser Lys Thr Thr Ala Thr Ala 485 490 495Ser Lys Thr Ser Thr Asp Asn Lys Phe Asn Lys Glu Gln Gln Asn Ala 500 505 510Phe Tyr Glu Ile Leu His Leu Pro Asn Leu Asn Glu Glu Gln Arg Asn 515 520 525Gly Phe Ile Gln Ser Leu Lys Asp Asp Pro Ser Gln Ser Ala Asn Leu 530 535 540Leu Ala Glu Ala Lys Lys Leu Asn Asp Ala Gln Ala Pro Lys Asp Asn545 550 555 560Lys Phe Asn Lys Glu Gln Gln Asn Ala Phe Tyr Glu Ile Leu His Leu 565 570 575Pro Asn Leu Asn Glu Glu Gln Arg Asn Gly Phe Ile Gln Ser Leu Lys 580 585 590Asp Asp Pro Ser Gln Ser Ala Asn Leu Leu Ala Glu Ala Lys Lys Leu 595 600 605Asn Asp Ala Gln Ala Pro Lys 610 61525559PRTArtificial Sequencefusion protein 25Ala Thr Leu Asp Ser Trp Leu Ser Asn Glu Ala Thr Val Ala Arg Thr1 5 10 15Ala Ile Leu Asn Asn Ile Gly Ala Asp Gly Ala Trp Val Ser Gly Ala 20 25 30Asp Ser Gly Ile Val Val Ala Ser Pro Ser Thr Asp Asn Pro Asp Tyr 35 40 45Phe Tyr Thr Trp Thr Arg Asp Ser Gly Leu Val Leu Lys Thr Leu Val 50 55 60Asp Leu Phe Arg Asn Gly Asp Thr Ser Leu Leu Ser Thr Ile Glu Asn65 70 75 80Tyr Ile Ser Ala Gln Ala Ile Val Gln Gly Ile Ser Asn Pro Ser Gly 85 90 95Asp Leu Ser Ser Gly Ala Gly Leu Gly Glu Pro Lys Phe Asn Val Asp 100 105 110Glu Thr Ala Tyr Thr Gly Ser Trp Gly Arg Pro Gln Arg Asp Gly Pro 115 120 125Ala Leu Arg Ala Thr Ala Met Ile Gly Phe Gly Gln Trp Leu Leu Asp 130 135 140Asn Gly Tyr Thr Ser Thr Ala Thr Asp Ile Val Trp Pro Leu Val Arg145 150 155 160Asn Asp Leu Ser Tyr Val Ala Gln Tyr Trp Asn Gln Thr Gly Tyr Asp 165 170 175Leu Trp Glu Glu Val Asn Gly Ser Ser Phe Phe Thr Ile Ala Val Gln 180 185 190His Arg Ala Leu Val Glu Gly Ser Ala Phe Ala Thr Ala Val Gly Ser 195 200 205Ser Cys Ser Trp Cys Asp Ser Gln Ala Pro Glu Ile Leu Cys Tyr Leu 210 215 220Gln Ser Phe Trp Thr Gly Ser Phe Ile Leu Ala Asn Phe Asp Ser Ser225 230 235 240Arg Ser Gly Lys Asp Ala Asn Thr Leu Leu Gly Ser Ile His Thr Phe 245 250 255Asp Pro Glu Ala Ala Cys Asp Asp Ser Thr Phe Gln Pro Cys Ser Pro 260 265 270Arg Ala Leu Ala Asn His Lys Glu Val Val Asp Ser Phe Arg Ser Ile 275 280 285Tyr Thr Leu Asn Asp Gly Leu Ser Asp Ser Glu Ala Val Ala Val Gly 290 295 300Arg Tyr Pro Glu Asp Thr Tyr Tyr Asn Gly Asn Pro Trp Phe Leu Cys305 310 315 320Thr Leu Ala Ala Ala Glu Gln Leu Tyr Asp Ala Leu Tyr Gln Trp Asp 325 330 335Lys Gln Gly Ser Leu Glu Val Thr Asp Val Ser Leu Asp Phe Phe Lys 340 345 350Ala Leu Tyr Ser Asp Ala Ala Thr Gly Thr Tyr Ser Ser Ser Ser Ser 355 360 365Thr Tyr Ser Ser Ile Val Asp Ala Val Lys Thr Phe Ala Asp Gly Phe 370 375 380Val Ser Ile Val Glu Thr His Ala Ala Ser Asn Gly Ser Met Ser Glu385 390 395 400Gln Tyr Asp Lys Ser Asp Gly Glu Gln Leu Ser Ala Arg Asp Leu Thr 405 410 415Trp Ser Tyr Ala Ala Leu Leu Thr Ala Asn Asn Arg Arg Asn Ser Val 420 425 430Val Pro Ala Ser Trp Gly Glu Thr Ser Ala Ser Ser Val Pro Gly Thr 435 440 445Cys Ala Ala Thr Ser Ala Ile Gly Thr Tyr Ser Ser Val Thr Val Thr 450 455 460Ser Trp Pro Ser Ile Val Ala Thr Gly Gly Thr Thr Thr Thr Ala Thr465 470 475 480Pro Thr Gly Ser Gly Ser Val Thr Ser Thr Ser Lys Thr Thr Ala Thr 485 490 495Ala Ser Lys Thr Ser Thr Asp Asn Lys Phe Asn Lys Glu Gln Gln Asn 500 505 510Ala Phe Tyr Glu Ile Leu His Leu Pro Asn Leu Asn Glu Glu Gln Arg 515 520 525Asn Gly Phe Ile Gln Ser Leu Lys Asp Asp Pro Ser Gln Ser Ala Asn 530 535 540Leu Leu Ala Glu Ala Lys Lys Leu Asn Asp Ala Gln Ala Pro Lys545 550 55526239PRTArtificial Sequencefusion protein 26Ala Val Trp Gly Gln Cys Gly Gly Ile Gly Phe Ser Gly Asp Thr Thr1 5 10 15Cys Thr Ala Ser Thr Cys Val Lys Val Asn Asp Tyr Tyr Ser Gln Cys 20 25 30Gln Pro Gly Ala Ser Ala Pro Thr Ser Thr Ala Ser Ala Pro Gly Pro 35 40 45Ser Ala Cys Pro Gly Ser Asp Asn Lys Phe Asn Lys Glu Gln Gln Asn 50 55 60Ala Phe Tyr Glu Ile Leu His Leu Pro Asn Leu Asn Glu Glu Gln Arg65 70 75 80Asn Gly Phe Ile Gln Ser Leu Lys Asp Asp Pro Ser Gln Ser Ala Asn 85 90 95Leu Leu Ala Glu Ala Lys Lys Leu Asn Asp Ala Gln Ala Pro Lys Asp 100 105 110Asn Lys Phe Asn Lys Glu Gln Gln Asn Ala Phe Tyr Glu Ile Leu His 115 120 125Leu Pro Asn Leu Asn Glu Glu Gln Arg Asn Gly Phe Ile Gln Ser Leu 130 135 140Lys Asp Asp Pro Ser Gln Ser Ala Asn Leu Leu Ala Glu Ala Lys Lys145 150 155 160Leu Asn Asp Ala Gln Ala Pro Lys Ser Ser Ser Thr Ser Ser Pro Val 165 170 175Asn Gln Pro Thr Ser Thr Ser Thr Thr Ser Thr Ser Thr Thr Ser Ser 180 185 190Pro Pro Val Gln Pro Thr Thr Pro Ser Gly Cys Thr Ala Glu Arg Trp 195 200 205Ala Gln Cys Gly Gly Asn Gly Trp Ser Gly Cys Thr Thr Cys Val Ala 210 215 220Gly Ser Thr Cys Thr Lys Ile Asn Asp Trp Tyr His Gln Cys Leu225 230 23527218PRTArtificial Sequencefusion protein 27Asp Asn Lys Phe Asn Lys Glu Gln Gln Asn Ala Phe Tyr Glu Ile Leu1 5 10 15His Leu Pro Asn Leu Asn Glu Glu Gln Arg Asn Gly Phe Ile Gln Ser 20 25 30Leu Lys Asp Asp Pro Ser Gln Ser Ala Asn Leu Leu Ala Glu Ala Lys 35 40 45Lys Leu Asn Asp Ala Gln Ala Pro Lys Asp Asn Lys Phe Asn Lys Glu 50 55 60Gln Gln Asn Ala Phe Tyr Glu Ile Leu His Leu Pro Asn Leu Asn Glu65 70 75 80Glu Gln Arg Asn Gly Phe Ile Gln Ser Leu Lys Asp Asp Pro Ser Gln 85 90 95Ser Ala Asn Leu Leu Ala Glu Ala Lys Lys Leu Asn Asp Ala Gln Ala 100 105 110Pro Lys Ala Val Trp Gly Gln Cys Gly Gly Ile Gly Phe Ser Gly Asp 115 120 125Thr Thr Cys Thr Ala Ser Thr Cys Val Lys Val Asn Asp Tyr Tyr Ser 130 135 140Gln Cys Gln Pro Gly Ala Ser Ala Pro Thr Ser Thr Ala Ser Ala Pro145 150 155 160Gly Pro Ser Ala Cys Pro Gly Ser Gln Ser Ser Pro Pro Val Gln Pro 165 170 175Thr Thr Pro Ser Gly Cys Thr Ala Glu Arg Trp Ala Gln Cys Gly Gly 180 185 190Asn Gly Trp Ser Gly Cys Thr Thr Cys Val Ala Gly Ser Thr Cys Thr 195

200 205Lys Ile Asn Asp Trp Tyr His Gln Cys Leu 210 21528185PRTArtificial Sequencefusion protein 28Gln Val Gln Leu Gln Glu Ser Gly Gly Gly Leu Val Gln Ala Gly Gly1 5 10 15Ser Leu Arg Leu Ser Cys Ala Ala Ser Gly Arg Ala Thr Ser Gly His 20 25 30Gly His Tyr Gly Met Gly Trp Phe Arg Gln Val Pro Gly Lys Glu Arg 35 40 45Glu Phe Val Ala Ala Ile Arg Trp Ser Gly Lys Glu Thr Trp Tyr Lys 50 55 60Asp Ser Val Lys Gly Arg Phe Thr Ile Ser Arg Asp Asn Ala Lys Thr65 70 75 80Thr Val Tyr Leu Gln Met Asn Ser Leu Lys Pro Glu Asp Thr Ala Val 85 90 95Tyr Tyr Cys Ala Ala Arg Pro Val Arg Val Asp Asp Ile Ser Leu Pro 100 105 110Val Gly Phe Asp Tyr Trp Gly Gln Gly Thr Gln Val Thr Val Ser Ser 115 120 125Asp Asn Lys Phe Asn Lys Glu Gln Gln Asn Ala Phe Tyr Glu Ile Leu 130 135 140His Leu Pro Asn Leu Asn Glu Glu Gln Arg Asn Gly Phe Ile Gln Ser145 150 155 160Leu Lys Asp Asp Pro Ser Gln Ser Ala Asn Leu Leu Ala Glu Ala Lys 165 170 175Lys Leu Asn Asp Ala Gln Ala Pro Lys 180 18529390DNAArtificial SequenceZ::Z domain coding sequence 29tcattctgca gcagcggcgg ataacaaatt taacaaagaa cagcagaacg cgttttatga 60aatcctgcat ctgccgaacc tgaacgaaga acagcgcaac gcgtttatcc agagcctgaa 120agatgatccg agccagagcg cgaacctgct ggcggaagcg aaaaaactga acgatgcgca 180ggcgccgaaa gtcgacaaca aatttaataa ggaacaacaa aacgccttct acgaaattct 240ccatctaccc aatcttaatg aagagcagcg caacgctttt attcaatcgc ttaaggacga 300tcccagccaa tcggcaaatc ttctggctga agctaaaaag cttaatgacg cgcaagctcc 360taaagtgtag tcgctagcgg ccgcttagtt 39030626DNAArtificial Sequencestreptavidin coding sequence 30aagcttaatg acgcgcaagc tcctaaagtg gacccgtcaa aagattccaa agcccaggta 60agtgcagctg aagcaggcat aacgggaaca tggtacaatc aactgggaag cacgtttatc 120gtaacagcag gagcggacgg agcgttgaca ggcacatacg aatctgccgt tggaaacgca 180gaatcgcgtt acacacttac aggtagatac gattcagcac cggctaccga tggaagcgga 240actgcattgg gatggagagt ggcttggaaa aacaactata gaaatgcgca tagcgccacg 300acatggtctg gccaatacgt cggaggagca gaagctagaa tcaatacaca atggacatta 360acgagcggga ctacagaagc aaatgcctgg aaatcgacgt taagaggtca tgataccttt 420accaaagtaa agccgtccgc agcatcaatt gatgcagcga agaaagcagg agtgaataac 480ggtaatcctt tggatgcagt gcaacaatag tcgctagcgg ccgcgtcgac tagaagagca 540gagaggacgg atttcctgaa ggaaatccgt ttttttattt tgcccgtctt ataaatttcg 600ttgagatctt gatcatcgat aagctt 626314084DNAArtificial Sequenceplasmid pSJ6208 31tcgcgcgttt cggtgatgac ggtgaaaacc tctgacacat gcagctcccg gagacggtca 60cagcttgtct gtaagcggat gccgggagca gacaagcccg tcagggcgcg tcagcgggtg 120ttggcgggtg tcggggctgg cttaactatg cggcatcaga gcagattgta ctgagagtgc 180accatatgcg gtgtgaaata ccgcacagat gcgtaaggag aaaataccgc atcaggcgcc 240attcgccatt caggctgcgc aactgttggg aagggcgatc ggtgcgggcc tcttcgctat 300tacgccagct ggcgaaaggg ggatgtgctg caaggcgatt aagttgggta acgccagggt 360tttcccagtc acgacgttgt aaaacgacgg ccagtgaatt cagatctaaa gataatatct 420ttgaattgta acscccctca aaagtaagaa ctacaaaaaa agaatacgtt atatagaaat 480atgtttgaac cttcttcaga ttacaaatat attcggacgg actctacctc aaatgcttat 540ctaactatag aatgacatac aagcacaacc ttgaaaattt gaaaatataa ctaccaatga 600acttgttcat gtgaattatc gctgtattta attttctcaa ttcaatatat aatatgccaa 660tacattgtta caagtagaaa ttaagacacc cttgatagcc ttactatacc taacatgatg 720tagtattaaa tgaatatgta aatatattta tgataagaag cgacttattt ataatcatta 780catatttttc tattggaatg attaagattc caatagaata gtgtataaat tatttatctt 840gaaaggaggg atgcctaaaa acgaagaaca ttaaaaacat atatttgcac cgtctaatgg 900atttatgaaa aatcatttta tcagtttgaa aattatgtat tatggccaca ttgaaagggg 960aggagaatca tgaaacaaca aaaacggctt tacgcccgat tgctgacgct gttatttgcg 1020ctcatcttct tgctgcctca ttctgcagca gcggcgatcg tcggcggtac gaaggccagt 1080acctcgacct acccgttcgt ggtcttcctg actgacagca ccggtttcca gttctgcggt 1140ggcacgctgg tcaagccgaa caaggtggtc acggcggcgc actgcaccgt cggtgagtcc 1200gcggccaaca tccgcgttgt cgccggtcgc gacgacaagc agagcaccgc cggcactgtc 1260tcgaaggtca gcaagatctg gatccacccg agttaccagg acgccaccaa gggcagcgac 1320gtgtcggtgc tgaccctgtc gaccagcctg acccagttca cgccgttgcc gctggctgcc 1380accactgaca ccgcgctgta caaggagggc accgccgcga ccatcctcgg ctggggtgac 1440accaccgagg gcgggtcggc ctctcggtac ctgctcaagg cgacagtgcc gctgaccagc 1500gacgccacct gcaagaaggc gtacggcgag tacagttcca ccgcgatggt ctgtgccgga 1560tacccgcagg gtggcacgga cacctgccag ggcgactccg gcggtccgct cgtcgccggc 1620aacaagctga tcggcatcac ctcgtggggc cagggctgcg ccgaggccgg ttatccaggc 1680gtctacaccc gggtcgccac ctacagttcg ctgatcaccc agcagctcgg ctagtcgcta 1740gcggccgcgt cgactagaag agcagagagg acggatttcc tgaaggaaat ccgttttttt 1800attttgcccg tcttataaat ttcgttgaga tcttgatcat cgataagctt ggcgtaatca 1860tggtcatagc tgtttcctgt gtgaaattgt tatccgctca caattccaca caacatacga 1920gccggaagca taaagtgtaa agcctggggt gcctaatgag tgagctaact cacattaatt 1980gcgttgcgct cactgcccgc tttccagtcg ggaaacctgt cgtgccagct gcattaatga 2040atcggccaac gcgcggggag aggcggtttg cgtattgggc gctcttccgc ttcctcgctc 2100actgactcgc tgcgctcggt cgttcggctg cggcgagcgg tatcagctca ctcaaaggcg 2160gtaatacggt tatccacaga atcaggggat aacgcaggaa agaacatgtg agcaaaaggc 2220cagcaaaagg ccaggaaccg taaaaaggcc gcgttgctgg cgtttttcca taggctccgc 2280ccccctgacg agcatcacaa aaatcgacgc tcaagtcaga ggtggcgaaa cccgacagga 2340ctataaagat accaggcgtt tccccctgga agctccctcg tgcgctctcc tgttccgacc 2400ctgccgctta ccggatacct gtccgccttt ctcccttcgg gaagcgtggc gctttctcaa 2460tgctcacgct gtaggtatct cagttcggtg taggtcgttc gctccaagct gggctgtgtg 2520cacgaacccc ccgttcagcc cgaccgctgc gccttatccg gtaactatcg tcttgagtcc 2580aacccggtaa gacacgactt atcgccactg gcagcagcca ctggtaacag gattagcaga 2640gcgaggtatg taggcggtgc tacagagttc ttgaagtggt ggcctaacta cggctacact 2700agaaggacag tatttggtat ctgcgctctg ctgaagccag ttaccttcgg aaaaagagtt 2760ggtagctctt gatccggcaa acaaaccacc gctggtagcg gtggtttttt tgtttgcaag 2820cagcagatta cgcgcagaaa aaaaggatct caagaagatc ctttgatctt ttctacgggg 2880tctgacgctc agtggaacga aaactcacgt taagggattt tggtcatgag attatcaaaa 2940aggatcttca cctagatcct tttaaattaa aaatgaagtt ttaaatcaat ctaaagtata 3000tatgagtaaa cttggtctga cagttaccaa tgcttaatca gtgaggcacc tatctcagcg 3060atctgtctat ttcgttcatc catagttgcc tgactccccg tcgtgtagat aactacgata 3120cgggagggct taccatctgg ccccagtgct gcaatgatac cgcgagaccc acgctcaccg 3180gctccagatt tatcagcaat aaaccagcca gccggaaggg ccgagcgcag aagtggtcct 3240gcaactttat ccgcctccat ccagtctatt aattgttgcc gggaagctag agtaagtagt 3300tcgccagtta atagtttgcg caacgttgtt gccattgcta caggcatcgt ggtgtcacgc 3360tcgtcgtttg gtatggcttc attcagctcc ggttcccaac gatcaaggcg agttacatga 3420tcccccatgt tgtgcaaaaa agcggttagc tccttcggtc ctccgatcgt tgtcagaagt 3480aagttggccg cagtgttatc actcatggtt atggcagcac tgcataattc tcttactgtc 3540atgccatccg taagatgctt ttctgtgact ggtgagtact caaccaagtc attctgagaa 3600tagtgtatgc ggcgaccgag ttgctcttgc ccggcgtcaa tacgggataa taccgcgcca 3660catagcagaa ctttaaaagt gctcatcatt ggaaaacgtt cttcggggcg aaaactctca 3720aggatcttac cgctgttgag atccagttcg atgtaaccca ctcgtgcacc caactgatct 3780tcagcatctt ttactttcac cagcgtttct gggtgagcaa aaacaggaag gcaaaatgcc 3840gcaaaaaagg gaataagggc gacacggaaa tgttgaatac tcatactctt cctttttcaa 3900tattattgaa gcatttatca gggttattgt ctcatgagcg gatacatatt tgaatgtatt 3960tagaaaaata aacaaatagg ggttccgcgc acatttcccc gaaaagtgcc acctgacgtc 4020taagaaacca ttattatcat gacattaacc tataaaaata ggcgtatcac gaggcccttt 4080cgtc 4084326691DNAArtificial SequencePlasmid sequence pSJ6321 32gaattcagat ctaaagataa tatctttgaa ttgtaacscc cctcaaaagt aagaactaca 60aaaaaagaat acgttatata gaaatatgtt tgaaccttct tcagattaca aatatattcg 120gacggactct acctcaaatg cttatctaac tatagaatga catacaagca caaccttgaa 180aatttgaaaa tataactacc aatgaacttg ttcatgtgaa ttatcgctgt atttaatttt 240ctcaattcaa tatataatat gccaatacat tgttacaagt agaaattaag acacccttga 300tagccttact atacctaaca tgatgtagta ttaaatgaat atgtaaatat atttatgata 360agaagcgact tatttataat cattacatat ttttctattg gaatgattaa gattccaata 420gaatagtgta taaattattt atcttgaaag gagggatgcc taaaaacgaa gaacattaaa 480aacatatatt tgcaccgtct aatggattta tgaaaaatca ttttatcagt ttgaaaatta 540tgtattatgg ccacattgaa aggggaggag aatcatgaaa caacaaaaac ggctttacgc 600ccgattgctg acgctgttat ttgcgctcat cttcttgctg cctcattctg cagcagcggc 660ggccaccgga gcgctccccc agtcacccac cccggaggcc gacgcggtct ccatgcagga 720ggcgctccag cgcgacctcg acctgacctc cgccgaggcc gaggagctgc tggccgccca 780ggacaccgcc ttcgaggtcg acgaggccgc ggccgaggcc gccggggacg cctacggcgg 840ctccgtcttc gacaccgaga gcctggaact gaccgtcctg gtcaccgatg ccgccgcggt 900cgaggccgtg gaggccaccg gcgccgggac cgagctggtc tcctacggca tcgacggtct 960cgacgagatc gtccaggagc tcaacgccgc cgacgccgtt cccggtgtgg tcggctggta 1020cccggacgtg gcgggtgaca ccgtcgtcct ggaggtcctg gagggttccg gagccgacgt 1080cagcggcctg ctcgcggacg ccggcgtgga cgcctcggcc gtcgaggtga ccacgagcga 1140ccagcccgag ctctacgccg acatcatcgg tggtctggcc tacaccatgg gcggccgctg 1200ttcggtcggc ttcgcggcca ccaacgccgc cggtcagccc gggttcgtca ccgccggtca 1260ctgcggccgc gtgggcaccc aggtgaccat cggcaacggc aggggcgtct tcgagcagtc 1320cgtcttcccc ggcaacgacg cggccttcgt ccgcggtacg tccaacttca cgctgaccaa 1380cctggtcagc cgctacaaca ccggcgggta cgccacggtc gccggtcaca accaggcccc 1440catcggctcc tccgtctgcc gctccggctc caccaccggt tggcactgcg gcaccatcca 1500ggcccgcggc cagtcggtga gctaccccga gggcaccgtc accaacatga cccggaccac 1560cgtgtgcgcc gagcccggcg actccggcgg ctcctacatc tccggcaccc aggcccaggg 1620cgtgacctcc ggcggctccg gcaactgccg caccggcggg accaccttct accaggaggt 1680cacccccatg gtgaactcct ggggcgtccg tctccggacc tgaacgcgtg ctagcggccg 1740cgtcgactag aagagcagag aggacggatt tcctgaagga aatccgtttt tttattttgc 1800ccgtcttata aatttcgttg agatctacgc gtccatgggc tagcgcggcc gcgtcgacag 1860gcctctttga ttacatttta taattaattt taacaaagtg tcatcagccc tcaggaagga 1920cttgctgaca gtttgaatcg cataggtaag gcggggatga aatggcaacg ttatctgatg 1980tagcaaagaa agcaaatgtg tcgaaaatga cggtatcgcg ggtgatcaat catcctgaga 2040ctgtgacgga tgaattgaaa aagcttgttc attccgcaat gaaggagctc aattatatac 2100cgaactatgc agcaagagcg ctcgttcaaa acagaacaca ggtcgtcaag ctgctcatac 2160tggaagaaat ggatacaaca gaaccttatt atatgaatct gttaacggga atcagccgcg 2220agctggaccg tcatcattat gctttgcagc ttgtcacaag gaaatctctc aatatcggcc 2280agtgcgacgg cattattgcg acggggttga gaaaagccga ttttgaaggg ctcatcaagg 2340tttttgaaaa gcgtgtcgtt gtattcggga cgtcgattca caaaaatagg cacacgaaaa 2400acaagtaagg gatgcagttt atgcatccct taacttactt attaaataat ttatagctat 2460tgaaaagaga taagaattgt tcaaagctaa tattgtttaa atcgtcaatt cctgcatgtt 2520ttaaggaatt gttaaattga ttttttgtaa atattttctt gtattctttg ttaacccatt 2580tcataacgaa ataattatac ttttgtttat ctttgtgtga tattcttgat ttttttctac 2640ttaatctgat aagtgagcta ttcactttag gtttaggatg aaaatattct cttggaacca 2700tacttaatat agaaatatca acttctgcca ttaaaagtaa tgccaatgag cgttttgtat 2760ttaataatct tttagcaaac ccgtattcca cgattaaata aatctcatta gctatactat 2820caaaaacaat tttgcgtatt atatccgtac ttatgttata aggtatatta ccatatattt 2880tataggattg gtttttagga aatttaaact gcaatatatc cttgtttaaa acttggaaat 2940tatcgtgatc aacaagttta ttttctgtag ttttgcataa tttatggtct atttcaatgg 3000cagttacgaa attacacctc tttactaatt caagggtaaa atggcctttt cctgagccga 3060tttcaaagat attatcatgt tcatttaatc ttatatttgt cattatttta tctatattat 3120gttttgaagt aataaagttt tgactgtgtt ttatattttt ctcgttcatt ataaccctct 3180ttaatttggt tatatgaatt ttgcttatta acgattcatt ataaccactt attttttgtt 3240tggttgataa tgaactgtgc tgattacaaa aatactaaaa atgcccatat tttttcctcc 3300ttataaaatt agtataatta tagcacgagc tctgataaat atgaacatga tgagtgatcg 3360ttaaatttat actgcaatcg gatgcgatta ttgaataaaa gatatgagag atttatctaa 3420tttctttttt cttgtaaaaa aagaaagttc ttaaaggttt tatagttttg gtcgtagagc 3480acacggttta acgacttaat tacgaagtaa ataagtctag tgtgttagac tttatgaaat 3540ctatatacgt ttatatatat ttattatccg gaggtgtagc atgtctcatt caattttgag 3600ggttgccaga gttaaaggat caagtaatac aaacgggata caaagacata atcaaagaga 3660gaataaaaac tataataata aagacataaa tcatgaggaa acatataaaa attatgattt 3720gattaacgca caaaatataa agtataaaga taaaattgat gaaacgattg atgagaatta 3780ttcagggaaa cgtaaaattc ggtcagatgc aattcgacat gtggacggac tggttacaag 3840tgataaagat ttctttgatg atttaagcgg agaagaaata gaacgatttt ttaaagatag 3900cttggagttt ctagaaaatg aatacggtaa ggaaaatatg ctgtatgcga ctgtccatct 3960ggatgaaaga gtcccacata tgcactttgg ttttgtccct ttaacagagg acgggagatt 4020gtctgcaaaa gaacagttag gcaacaagaa agactttact caattacaag atagatttaa 4080tgagtatgtg aatgagaaag gttatgaact tgaaagaggc acgtccaaag aggttacaga 4140acgagaacat aaagcgatgg atcagtacaa gaaagatact gtatttcata aacaggaact 4200gcaagaagtt aaggatgagt tacagaaggc aaataagcag ttacagagtg gaatagagca 4260tatgaggtct acgaaaccct ttgattatga aaatgagcgt acaggtttgt tctctggacg 4320tgaagagact ggtagaaaga tattaactgc tgatgaattt gaacgcctgc aagaaacaat 4380ctcttctgca gaacggattg ttgatgatta cgaaaatatt aagagcacag actattacac 4440agaaaatcaa gaattaaaaa aacgtagaga gagtttgaaa gaagtagtga atacatggaa 4500agaggggtat cacgaaaaaa gtaaagaggt taataaatta aagcgagaga atgatagttt 4560gaatgagcag ttgaatgtat cagagaaatt tcaagctagt acagtgactt tatatcgtgc 4620tgcgagggcg aatttccctg ggtttgagaa agggtttaat aggcttaaag agaaattctt 4680taatgattcc aaatttgagc gtgtgggaca gtttatggat gttgtacagg ataatgtcca 4740gaaggtcgat agaaagcgtg agaaacagcg tacagacgat ttagagatgt agaggtactt 4800ttatgccgag aaaacttttt gcgtgtgaca gtccttaaaa tatacttaga gcgtaagcga 4860aagtagtagc gacagctatt aactttcggt ttcaaagctc taggattttt aatggacgca 4920gcgcatcaca cgcaaaaagg aaattggaat aaatgcgaaa tttgagatgt taattaaaga 4980cctttttgag gtcttttttt cttagatttt tggggttatt taggggagaa aacatagggg 5040ggtactacga cctcccccct aggtgtccat tgtccattgt ccaaacaaat aaataaatat 5100tgggttttta atgttaaaag gttgtttttt atgttaaagt gaaaaaaaca gatgttggga 5160ggtacagtga tggttgtaga tagaaaagaa gagaaaaaag ttgctgttac tttaagactt 5220acaacagaag aaaatgagat attaaataga atcaaagaaa aatataatat tagcaaatca 5280gatgcaaccg gtattctaat aaaaaaatat gcaaaggagg aatacggtgc attttaaaca 5340aaaaaagata gacagcactg gcatgctgcc tatctatgac taaattttgt taagtgtatt 5400agcaccgtta ttatatcatg agcgaaaatg taataaaaga aactgaaaac aagaaaaatt 5460caagaggacg taattggaca tttgttttat atccagaatc agcaaaagcc gagtggttag 5520agtatttaaa agagttacac attcaatttg tagtgtctcc attacatgat agggatactg 5580atacagaagg taggatgaaa aaagagcatt atcatattct agtgatgtat gagggtaata 5640aatcttatga acagataaaa ataattacag aagaattgaa tgcgactatt ccgcagattg 5700caggaagtgt gaaaggtctt gtgagatata tgcttcacat ggacgatcct aataaattta 5760aatatcaaaa agaagatatg atagtttatg gcggtgtaga tgttgatgaa ttattaaaga 5820aaacaacaac agatagatat aaattaatta aagaaatgat tgagtttatt gatgaacaag 5880gaatcgtaga atttaagagt ttaatggatt atgcaatgaa gtttaaattt gatgattggt 5940tcccgctttt atgtgataac tcggcgtatg ttattcaaga atatataaaa tcaaatcggt 6000ataaatctga ccgatagatt ttgaatttag gtgtcacaag acactctttt ttcgcaccag 6060cgaaaactgg tttaagccga ctgcgcaaaa gacataatcg actctagagg atccccgggt 6120accgagctct gccttttagt ccagctgatt tcactttttg cattctacaa actgcataac 6180tcatatgtaa atcgctcctt tttaggtggc acaaatgtga ggcattttcg ctctttccgg 6240caaccacttc caagtaaagt ataacacact atactttata ttcataaagt gtgtgctctg 6300cgaggctgtc ggcagtgccg accaaaacca taaaaccttt aagacctttc ttttttttac 6360gagaaaaaag aaacaaaaaa acctgccctc tgccacctca gcaaaggggg gttttgctct 6420cgtgctcgtt taaaaatcag caagggacag gtagtatttt ttgagaagat cactcaaaaa 6480atctccacct ttaaaccctt gccaattttt attttgtccg ttttgtctag cttaccgaaa 6540gccagactca gcaagaataa aatttttatt gtctttcggt tttctagtgt aacggacaaa 6600accactcaaa ataaaaaaga tacaagagag gtctctcgta tcttttattc agcaatcgcg 6660cccgattgct gaacagatta ataatgagct c 6691333757DNAArtificial SequencePlasmid sequence pMOL2743 33tcgcgcgttt cggtgatgac ggtgaaaacc tctgacacat gcagctcccg gagacggtca 60cagcttgtct gtaagcggat gccgggagca gacaagcccg tcagggcgcg tcagcgggtg 120ttggcgggtg tcggggctgg cttaactatg cggcatcaga gcagattgta ctgagagtgc 180accatatgcg gtgtgaaata ccgcacagat gcgtaaggag aaaataccgc atcaggcgcc 240attcgccatt caggctgcgc aactgttggg aagggcgatc ggtgcgggcc tcttcgctat 300tacgccagct ggcgaaaggg ggatgtgctg caaggcgatt aagttgggta acgccagggt 360tttcccagtc acgacgttgt aaaacgacgg ccagtgaatt cagatctaaa gataatatct 420ttgaattgta acscccctca aaagtaagaa ctacaaaaaa agaatacgtt atatagaaat 480atgtttgaac cttcttcaga ttacaaatat attcggacgg actctacctc aaatgcttat 540ctaactatag aatgacatac aagcacaacc ttgaaaattt gaaaatataa ctaccaatga 600acttgttcat gtgaattatc gctgtattta attttctcaa ttcaatatat aatatgccaa 660tacattgtta caagtagaaa ttaagacacc cttgatagcc ttactatacc taacatgatg 720tagtattaaa tgaatatgta aatatattta tgataagaag cgacttattt ataatcatta 780catatttttc tattggaatg attaagattc caatagaata gtgtataaat tatttatctt 840gaaaggaggg atgcctaaaa acgaagaaca ttaaaaacat atatttgcac cgtctaatgg 900atttatgaaa aatcatttta tcagtttgaa aattatgtat tatggccaca ttgaaagggg 960aggagaatca tgaaacaaca aaaacggctt tacgcccgat tgctgacgct gttatttgcg 1020ctcatcttct tgctgcctca ttctgcagca gcggcggata acaaatttaa caaagaacag 1080cagaacgcgt tttatgaaat cctgcatctg ccgaacctga acgaagaaca gcgcaacgcg 1140tttatccaga gcctgaaaga tgatccgagc cagagcgcga acctgctggc ggaagcgaaa 1200aaactgaacg atgcgcaggc gccgaaagtc gacaacaaat ttaataagga acaacaaaac 1260gccttctacg aaattctcca tctacccaat cttaatgaag agcagcgcaa cgcttttatt 1320caatcgctta aggacgatcc cagccaatcg gcaaatcttc tggctgaagc taaaaagctt 1380aatgacgcgc aagctcctaa agtgtagtcg ctagcggccg cgtcgactag aagagcagag 1440aggacggatt tcctgaagga aatccgtttt tttattttgc ccgtcttata aatttcgttg 1500agatcttgat catcgataag cttggcgtaa tcatggtcat agctgtttcc tgtgtgaaat 1560tgttatccgc tcacaattcc acacaacata cgagccggaa gcataaagtg taaagcctgg 1620ggtgcctaat

gagtgagcta actcacatta attgcgttgc gctcactgcc cgctttccag 1680tcgggaaacc tgtcgtgcca gctgcattaa tgaatcggcc aacgcgcggg gagaggcggt 1740ttgcgtattg ggcgctcttc cgcttcctcg ctcactgact cgctgcgctc ggtcgttcgg 1800ctgcggcgag cggtatcagc tcactcaaag gcggtaatac ggttatccac agaatcaggg 1860gataacgcag gaaagaacat gtgagcaaaa ggccagcaaa aggccaggaa ccgtaaaaag 1920gccgcgttgc tggcgttttt ccataggctc cgcccccctg acgagcatca caaaaatcga 1980cgctcaagtc agaggtggcg aaacccgaca ggactataaa gataccaggc gtttccccct 2040ggaagctccc tcgtgcgctc tcctgttccg accctgccgc ttaccggata cctgtccgcc 2100tttctccctt cgggaagcgt ggcgctttct caatgctcac gctgtaggta tctcagttcg 2160gtgtaggtcg ttcgctccaa gctgggctgt gtgcacgaac cccccgttca gcccgaccgc 2220tgcgccttat ccggtaacta tcgtcttgag tccaacccgg taagacacga cttatcgcca 2280ctggcagcag ccactggtaa caggattagc agagcgaggt atgtaggcgg tgctacagag 2340ttcttgaagt ggtggcctaa ctacggctac actagaagga cagtatttgg tatctgcgct 2400ctgctgaagc cagttacctt cggaaaaaga gttggtagct cttgatccgg caaacaaacc 2460accgctggta gcggtggttt ttttgtttgc aagcagcaga ttacgcgcag aaaaaaagga 2520tctcaagaag atcctttgat cttttctacg gggtctgacg ctcagtggaa cgaaaactca 2580cgttaaggga ttttggtcat gagattatca aaaaggatct tcacctagat ccttttaaat 2640taaaaatgaa gttttaaatc aatctaaagt atatatgagt aaacttggtc tgacagttac 2700caatgcttaa tcagtgaggc acctatctca gcgatctgtc tatttcgttc atccatagtt 2760gcctgactcc ccgtcgtgta gataactacg atacgggagg gcttaccatc tggccccagt 2820gctgcaatga taccgcgaga cccacgctca ccggctccag atttatcagc aataaaccag 2880ccagccggaa gggccgagcg cagaagtggt cctgcaactt tatccgcctc catccagtct 2940attaattgtt gccgggaagc tagagtaagt agttcgccag ttaatagttt gcgcaacgtt 3000gttgccattg ctacaggcat cgtggtgtca cgctcgtcgt ttggtatggc ttcattcagc 3060tccggttccc aacgatcaag gcgagttaca tgatccccca tgttgtgcaa aaaagcggtt 3120agctccttcg gtcctccgat cgttgtcaga agtaagttgg ccgcagtgtt atcactcatg 3180gttatggcag cactgcataa ttctcttact gtcatgccat ccgtaagatg cttttctgtg 3240actggtgagt actcaaccaa gtcattctga gaatagtgta tgcggcgacc gagttgctct 3300tgcccggcgt caatacggga taataccgcg ccacatagca gaactttaaa agtgctcatc 3360attggaaaac gttcttcggg gcgaaaactc tcaaggatct taccgctgtt gagatccagt 3420tcgatgtaac ccactcgtgc acccaactga tcttcagcat cttttacttt caccagcgtt 3480tctgggtgag caaaaacagg aaggcaaaat gccgcaaaaa agggaataag ggcgacacgg 3540aaatgttgaa tactcatact cttccttttt caatattatt gaagcattta tcagggttat 3600tgtctcatga gcggatacat atttgaatgt atttagaaaa ataaacaaat aggggttccg 3660cgcacatttc cccgaaaagt gccacctgac gtctaagaaa ccattattat catgacatta 3720acctataaaa ataggcgtat cacgaggccc tttcgtc 3757344234DNAArtificial Sequenceplasmid sequence pMOL2744 34tcgcgcgttt cggtgatgac ggtgaaaacc tctgacacat gcagctcccg gagacggtca 60cagcttgtct gtaagcggat gccgggagca gacaagcccg tcagggcgcg tcagcgggtg 120ttggcgggtg tcggggctgg cttaactatg cggcatcaga gcagattgta ctgagagtgc 180accatatgcg gtgtgaaata ccgcacagat gcgtaaggag aaaataccgc atcaggcgcc 240attcgccatt caggctgcgc aactgttggg aagggcgatc ggtgcgggcc tcttcgctat 300tacgccagct ggcgaaaggg ggatgtgctg caaggcgatt aagttgggta acgccagggt 360tttcccagtc acgacgttgt aaaacgacgg ccagtgaatt cagatctaaa gataatatct 420ttgaattgta acscccctca aaagtaagaa ctacaaaaaa agaatacgtt atatagaaat 480atgtttgaac cttcttcaga ttacaaatat attcggacgg actctacctc aaatgcttat 540ctaactatag aatgacatac aagcacaacc ttgaaaattt gaaaatataa ctaccaatga 600acttgttcat gtgaattatc gctgtattta attttctcaa ttcaatatat aatatgccaa 660tacattgtta caagtagaaa ttaagacacc cttgatagcc ttactatacc taacatgatg 720tagtattaaa tgaatatgta aatatattta tgataagaag cgacttattt ataatcatta 780catatttttc tattggaatg attaagattc caatagaata gtgtataaat tatttatctt 840gaaaggaggg atgcctaaaa acgaagaaca ttaaaaacat atatttgcac cgtctaatgg 900atttatgaaa aatcatttta tcagtttgaa aattatgtat tatggccaca ttgaaagggg 960aggagaatca tgaaacaaca aaaacggctt tacgcccgat tgctgacgct gttatttgcg 1020ctcatcttct tgctgcctca ttctgcagca gcggcggata acaaatttaa caaagaacag 1080cagaacgcgt tttatgaaat cctgcatctg ccgaacctga acgaagaaca gcgcaacgcg 1140tttatccaga gcctgaaaga tgatccgagc cagagcgcga acctgctggc ggaagcgaaa 1200aaactgaacg atgcgcaggc gccgaaagtc gacaacaaat ttaataagga acaacaaaac 1260gccttctacg aaattctcca tctacccaat cttaatgaag agcagcgcaa cgcttttatt 1320caatcgctta aggacgatcc cagccaatcg gcaaatcttc tggctgaagc taaaaagctt 1380aatgacgcgc aagctcctaa agtggacccg tcaaaagatt ccaaagccca ggtaagtgca 1440gctgaagcag gcataacggg aacatggtac aatcaactgg gaagcacgtt tatcgtaaca 1500gcaggagcgg acggagcgtt gacaggcaca tacgaatctg ccgttggaaa cgcagaatcg 1560cgttacacac ttacaggtag atacgattca gcaccggcta ccgatggaag cggaactgca 1620ttgggatgga gagtggcttg gaaaaacaac tatagaaatg cgcatagcgc cacgacatgg 1680tctggccaat acgtcggagg agcagaagct agaatcaata cacaatggac attaacgagc 1740gggactacag aagcaaatgc ctggaaatcg acgttaagag gtcatgatac ctttaccaaa 1800gtaaagccgt ccgcagcatc aattgatgca gcgaagaaag caggagtgaa taacggtaat 1860cctttggatg cagtgcaaca atagtcgcta gcggccgcgt cgactagaag agcagagagg 1920acggatttcc tgaaggaaat ccgttttttt attttgcccg tcttataaat ttcgttgaga 1980tcttgatcat cgataagctt ggcgtaatca tggtcatagc tgtttcctgt gtgaaattgt 2040tatccgctca caattccaca caacatacga gccggaagca taaagtgtaa agcctggggt 2100gcctaatgag tgagctaact cacattaatt gcgttgcgct cactgcccgc tttccagtcg 2160ggaaacctgt cgtgccagct gcattaatga atcggccaac gcgcggggag aggcggtttg 2220cgtattgggc gctcttccgc ttcctcgctc actgactcgc tgcgctcggt cgttcggctg 2280cggcgagcgg tatcagctca ctcaaaggcg gtaatacggt tatccacaga atcaggggat 2340aacgcaggaa agaacatgtg agcaaaaggc cagcaaaagg ccaggaaccg taaaaaggcc 2400gcgttgctgg cgtttttcca taggctccgc ccccctgacg agcatcacaa aaatcgacgc 2460tcaagtcaga ggtggcgaaa cccgacagga ctataaagat accaggcgtt tccccctgga 2520agctccctcg tgcgctctcc tgttccgacc ctgccgctta ccggatacct gtccgccttt 2580ctcccttcgg gaagcgtggc gctttctcaa tgctcacgct gtaggtatct cagttcggtg 2640taggtcgttc gctccaagct gggctgtgtg cacgaacccc ccgttcagcc cgaccgctgc 2700gccttatccg gtaactatcg tcttgagtcc aacccggtaa gacacgactt atcgccactg 2760gcagcagcca ctggtaacag gattagcaga gcgaggtatg taggcggtgc tacagagttc 2820ttgaagtggt ggcctaacta cggctacact agaaggacag tatttggtat ctgcgctctg 2880ctgaagccag ttaccttcgg aaaaagagtt ggtagctctt gatccggcaa acaaaccacc 2940gctggtagcg gtggtttttt tgtttgcaag cagcagatta cgcgcagaaa aaaaggatct 3000caagaagatc ctttgatctt ttctacgggg tctgacgctc agtggaacga aaactcacgt 3060taagggattt tggtcatgag attatcaaaa aggatcttca cctagatcct tttaaattaa 3120aaatgaagtt ttaaatcaat ctaaagtata tatgagtaaa cttggtctga cagttaccaa 3180tgcttaatca gtgaggcacc tatctcagcg atctgtctat ttcgttcatc catagttgcc 3240tgactccccg tcgtgtagat aactacgata cgggagggct taccatctgg ccccagtgct 3300gcaatgatac cgcgagaccc acgctcaccg gctccagatt tatcagcaat aaaccagcca 3360gccggaaggg ccgagcgcag aagtggtcct gcaactttat ccgcctccat ccagtctatt 3420aattgttgcc gggaagctag agtaagtagt tcgccagtta atagtttgcg caacgttgtt 3480gccattgcta caggcatcgt ggtgtcacgc tcgtcgtttg gtatggcttc attcagctcc 3540ggttcccaac gatcaaggcg agttacatga tcccccatgt tgtgcaaaaa agcggttagc 3600tccttcggtc ctccgatcgt tgtcagaagt aagttggccg cagtgttatc actcatggtt 3660atggcagcac tgcataattc tcttactgtc atgccatccg taagatgctt ttctgtgact 3720ggtgagtact caaccaagtc attctgagaa tagtgtatgc ggcgaccgag ttgctcttgc 3780ccggcgtcaa tacgggataa taccgcgcca catagcagaa ctttaaaagt gctcatcatt 3840ggaaaacgtt cttcggggcg aaaactctca aggatcttac cgctgttgag atccagttcg 3900atgtaaccca ctcgtgcacc caactgatct tcagcatctt ttactttcac cagcgtttct 3960gggtgagcaa aaacaggaag gcaaaatgcc gcaaaaaagg gaataagggc gacacggaaa 4020tgttgaatac tcatactctt cctttttcaa tattattgaa gcatttatca gggttattgt 4080ctcatgagcg gatacatatt tgaatgtatt tagaaaaata aacaaatagg ggttccgcgc 4140acatttcccc gaaaagtgcc acctgacgtc taagaaacca ttattatcat gacattaacc 4200tataaaaata ggcgtatcac gaggcccttt cgtc 4234356453DNAArtificial Sequenceplasmid sequence pMOL2746b 35gaattcagat ctaaagataa tatctttgaa ttgtaacscc cctcaaaagt aagaactaca 60aaaaaagaat acgttatata gaaatatgtt tgaaccttct tcagattaca aatatattcg 120gacggactct acctcaaatg cttatctaac tatagaatga catacaagca caaccttgaa 180aatttgaaaa tataactacc aatgaacttg ttcatgtgaa ttatcgctgt atttaatttt 240ctcaattcaa tatataatat gccaatacat tgttacaagt agaaattaag acacccttga 300tagccttact atacctaaca tgatgtagta ttaaatgaat atgtaaatat atttatgata 360agaagcgact tatttataat cattacatat ttttctattg gaatgattaa gattccaata 420gaatagtgta taaattattt atcttgaaag gagggatgcc taaaaacgaa gaacattaaa 480aacatatatt tgcaccgtct aatggattta tgaaaaatca ttttatcagt ttgaaaatta 540tgtattatgg ccacattgaa aggggaggag aatcatgaaa caacaaaaac ggctttacgc 600ccgattgctg acgctgttat ttgcgctcat cttcttgctg cctcattctg cagcagcggc 660ggataacaaa tttaacaaag aacagcagaa cgcgttttat gaaatcctgc atctgccgaa 720cctgaacgaa gaacagcgca acgcgtttat ccagagcctg aaagatgatc cgagccagag 780cgcgaacctg ctggcggaag cgaaaaaact gaacgatgcg caggcgccga aagtcgacaa 840caaatttaat aaggaacaac aaaacgcctt ctacgaaatt ctccatctac ccaatcttaa 900tgaagagcag cgcaacgctt ttattcaatc gcttaaggac gatcccagcc aatcggcaaa 960tcttctggct gaagctaaaa agcttaatga cgcgcaagct cctaaagtgg acccgtcaaa 1020agattccaaa gcccaggtaa gtgcagctga agcaggcata acgggaacat ggtacaatca 1080actgggaagc acgtttatcg taacagcagg agcggacgga gcgttgacag gcacatacga 1140atctgccgtt ggaaacgcag aatcgcgtta cacacttaca ggtagatacg attcagcacc 1200ggctaccgat ggaagcggaa ctgcattggg atggagagtg gcttggaaaa acaactatag 1260aaatgcgcat agcgccacga catggtctgg ccaatacgtc ggaggagcag aagctagaat 1320caatacacaa tggacattaa cgagcgggac tacagaagca aatgcctgga aatcgacgtt 1380aagaggtcat gataccttta ccaaagtaaa gccgtccgca gcatcaattg atgcagcgaa 1440gaaagcagga gtgaataacg gtaatccttt ggatgcagtg caacaatagt cgctagcggc 1500cgcgtcgact agaagagcag agaggacgga tttcctgaag gaaatccgtt tttttatttt 1560gcccgtctta taaatttcgt tgagatctac gcgtccatgg gctagcgcgg ccgcgtcgac 1620aggcctcttt gattacattt tataattaat tttaacaaag tgtcatcagc cctcaggaag 1680gacttgctga cagtttgaat cgcataggta aggcggggat gaaatggcaa cgttatctga 1740tgtagcaaag aaagcaaatg tgtcgaaaat gacggtatcg cgggtgatca atcatcctga 1800gactgtgacg gatgaattga aaaagcttgt tcattccgca atgaaggagc tcaattatat 1860accgaactat gcagcaagag cgctcgttca aaacagaaca caggtcgtca agctgctcat 1920actggaagaa atggatacaa cagaacctta ttatatgaat ctgttaacgg gaatcagccg 1980cgagctggac cgtcatcatt atgctttgca gcttgtcaca aggaaatctc tcaatatcgg 2040ccagtgcgac ggcattattg cgacggggtt gagaaaagcc gattttgaag ggctcatcaa 2100ggtttttgaa aagcgtgtcg ttgtattcgg gacgtcgatt cacaaaaata ggcacacgaa 2160aaacaagtaa gggatgcagt ttatgcatcc cttaacttac ttattaaata atttatagct 2220attgaaaaga gataagaatt gttcaaagct aatattgttt aaatcgtcaa ttcctgcatg 2280ttttaaggaa ttgttaaatt gattttttgt aaatattttc ttgtattctt tgttaaccca 2340tttcataacg aaataattat acttttgttt atctttgtgt gatattcttg atttttttct 2400acttaatctg ataagtgagc tattcacttt aggtttagga tgaaaatatt ctcttggaac 2460catacttaat atagaaatat caacttctgc cattaaaagt aatgccaatg agcgttttgt 2520atttaataat cttttagcaa acccgtattc cacgattaaa taaatctcat tagctatact 2580atcaaaaaca attttgcgta ttatatccgt acttatgtta taaggtatat taccatatat 2640tttataggat tggtttttag gaaatttaaa ctgcaatata tccttgttta aaacttggaa 2700attatcgtga tcaacaagtt tattttctgt agttttgcat aatttatggt ctatttcaat 2760ggcagttacg aaattacacc tctttactaa ttcaagggta aaatggcctt ttcctgagcc 2820gatttcaaag atattatcat gttcatttaa tcttatattt gtcattattt tatctatatt 2880atgttttgaa gtaataaagt tttgactgtg ttttatattt ttctcgttca ttataaccct 2940ctttaatttg gttatatgaa ttttgcttat taacgattca ttataaccac ttattttttg 3000tttggttgat aatgaactgt gctgattaca aaaatactaa aaatgcccat attttttcct 3060ccttataaaa ttagtataat tatagcacga gctctgataa atatgaacat gatgagtgat 3120cgttaaattt atactgcaat cggatgcgat tattgaataa aagatatgag agatttatct 3180aatttctttt ttcttgtaaa aaaagaaagt tcttaaaggt tttatagttt tggtcgtaga 3240gcacacggtt taacgactta attacgaagt aaataagtct agtgtgttag actttatgaa 3300atctatatac gtttatatat atttattatc cggaggtgta gcatgtctca ttcaattttg 3360agggttgcca gagttaaagg atcaagtaat acaaacggga tacaaagaca taatcaaaga 3420gagaataaaa actataataa taaagacata aatcatgagg aaacatataa aaattatgat 3480ttgattaacg cacaaaatat aaagtataaa gataaaattg atgaaacgat tgatgagaat 3540tattcaggga aacgtaaaat tcggtcagat gcaattcgac atgtggacgg actggttaca 3600agtgataaag atttctttga tgatttaagc ggagaagaaa tagaacgatt ttttaaagat 3660agcttggagt ttctagaaaa tgaatacggt aaggaaaata tgctgtatgc gactgtccat 3720ctggatgaaa gagtcccaca tatgcacttt ggttttgtcc ctttaacaga ggacgggaga 3780ttgtctgcaa aagaacagtt aggcaacaag aaagacttta ctcaattaca agatagattt 3840aatgagtatg tgaatgagaa aggttatgaa cttgaaagag gcacgtccaa agaggttaca 3900gaacgagaac ataaagcgat ggatcagtac aagaaagata ctgtatttca taaacaggaa 3960ctgcaagaag ttaaggatga gttacagaag gcaaataagc agttacagag tggaatagag 4020catatgaggt ctacgaaacc ctttgattat gaaaatgagc gtacaggttt gttctctgga 4080cgtgaagaga ctggtagaaa gatattaact gctgatgaat ttgaacgcct gcaagaaaca 4140atctcttctg cagaacggat tgttgatgat tacgaaaata ttaagagcac agactattac 4200acagaaaatc aagaattaaa aaaacgtaga gagagtttga aagaagtagt gaatacatgg 4260aaagaggggt atcacgaaaa aagtaaagag gttaataaat taaagcgaga gaatgatagt 4320ttgaatgagc agttgaatgt atcagagaaa tttcaagcta gtacagtgac tttatatcgt 4380gctgcgaggg cgaatttccc tgggtttgag aaagggttta ataggcttaa agagaaattc 4440tttaatgatt ccaaatttga gcgtgtggga cagtttatgg atgttgtaca ggataatgtc 4500cagaaggtcg atagaaagcg tgagaaacag cgtacagacg atttagagat gtagaggtac 4560ttttatgccg agaaaacttt ttgcgtgtga cagtccttaa aatatactta gagcgtaagc 4620gaaagtagta gcgacagcta ttaactttcg gtttcaaagc tctaggattt ttaatggacg 4680cagcgcatca cacgcaaaaa ggaaattgga ataaatgcga aatttgagat gttaattaaa 4740gacctttttg aggtcttttt ttcttagatt tttggggtta tttaggggag aaaacatagg 4800ggggtactac gacctccccc ctaggtgtcc attgtccatt gtccaaacaa ataaataaat 4860attgggtttt taatgttaaa aggttgtttt ttatgttaaa gtgaaaaaaa cagatgttgg 4920gaggtacagt gatggttgta gatagaaaag aagagaaaaa agttgctgtt actttaagac 4980ttacaacaga agaaaatgag atattaaata gaatcaaaga aaaatataat attagcaaat 5040cagatgcaac cggtattcta ataaaaaaat atgcaaagga ggaatacggt gcattttaaa 5100caaaaaaaga tagacagcac tggcatgctg cctatctatg actaaatttt gttaagtgta 5160ttagcaccgt tattatatca tgagcgaaaa tgtaataaaa gaaactgaaa acaagaaaaa 5220ttcaagagga cgtaattgga catttgtttt atatccagaa tcagcaaaag ccgagtggtt 5280agagtattta aaagagttac acattcaatt tgtagtgtct ccattacatg atagggatac 5340tgatacagaa ggtaggatga aaaaagagca ttatcatatt ctagtgatgt atgagggtaa 5400taaatcttat gaacagataa aaataattac agaagaattg aatgcgacta ttccgcagat 5460tgcaggaagt gtgaaaggtc ttgtgagata tatgcttcac atggacgatc ctaataaatt 5520taaatatcaa aaagaagata tgatagttta tggcggtgta gatgttgatg aattattaaa 5580gaaaacaaca acagatagat ataaattaat taaagaaatg attgagttta ttgatgaaca 5640aggaatcgta gaatttaaga gtttaatgga ttatgcaatg aagtttaaat ttgatgattg 5700gttcccgctt ttatgtgata actcggcgta tgttattcaa gaatatataa aatcaaatcg 5760gtataaatct gaccgataga ttttgaattt aggtgtcaca agacactctt ttttcgcacc 5820agcgaaaact ggtttaagcc gactgcgcaa aagacataat cgactctaga ggatccccgg 5880gtaccgagct ctgcctttta gtccagctga tttcactttt tgcattctac aaactgcata 5940actcatatgt aaatcgctcc tttttaggtg gcacaaatgt gaggcatttt cgctctttcc 6000ggcaaccact tccaagtaaa gtataacaca ctatacttta tattcataaa gtgtgtgctc 6060tgcgaggctg tcggcagtgc cgaccaaaac cataaaacct ttaagacctt tctttttttt 6120acgagaaaaa agaaacaaaa aaacctgccc tctgccacct cagcaaaggg gggttttgct 6180ctcgtgctcg tttaaaaatc agcaagggac aggtagtatt ttttgagaag atcactcaaa 6240aaatctccac ctttaaaccc ttgccaattt ttattttgtc cgttttgtct agcttaccga 6300aagccagact cagcaagaat aaaattttta ttgtctttcg gttttctagt gtaacggaca 6360aaaccactca aaataaaaaa gatacaagag aggtctctcg tatcttttat tcagcaatcg 6420cgcccgattg ctgaacagat taataatgag ctc 64533662DNAArtificial SequencePrimer 36tcattctgca gcagcggcgg ataacaaatt taacaaagaa cagcagaacg cgttttatga 60aa 623752DNAArtificial SequencePrimer 37aactaagcgg ccgctagcga ctacacttta ggagcttgcg cgtcattaag ct 52381062DNAArtificial SequenceORF of protein A fused to streptavidin 38atgaaacaac aaaaacggct ttacgcccga ttgctgacgc tgttatttgc gctcatcttc 60ttgctgcctc attctgcagc cgcggcagac ccctccaagg actcgaaggc ccaggtctcg 120gccgccgagg ccggcatcac cggcacctgg tacaaccagc tcggctcgac cttcatcgtg 180accgcgggcg ccgacggcgc cctgaccgga acctacgagt cggccgtcgg caacgccgag 240agccgctacg tcctgaccgg tcgttacgac agcgccccgg ccaccgacgg cagcggcacc 300gccctcggtt ggacggtggc ctggaagaat aactaccgca acgcccactc cgcgaccacg 360tggagcggcc agtacgtcgg cggcgccgag gcgaggatca acacccagtg gctgctgacc 420tccggcacca ccgaggccaa cgcctggaag tccacgctgg tcggccacga caccttcacc 480aaggtgaagc cgtccgccgc ctccatcgac gcggcgaaga aggccggcgt caacaacggc 540aacccgctcg acgccgttca gcagtcgaca ttacttatat ctggtggcgt aacacctgct 600gcaaatgctg cgcaacacga tgaagctcaa caaaatgctt tttatcaagt cttaaatatg 660cctaacttaa atgctgatca acgcaatggt tttatccaaa gccttaaaga tgatccaagc 720caaagtgcta acgttttagg tgaagctcaa aaacttaatg actctcaagc tccaaaagct 780gatgcgcaac aaaataactt caacaaagat caacaaagcg ccttctatga aatcttgaac 840atgcctaact taaacgaagc gcaacgtaac ggcttcattc aaagtcttaa agacgaccca 900agccaaagca ctaacgtttt aggtgaagct aaaaaattaa acgaatctca agcaccgaaa 960gctgataaca atttcaacaa agaacaacaa aatgctttct atgaaatctt gaatatgcct 1020aacttaaacg aagaacaacg caatggtttc atccaaagct ta 106239354PRTArtificial SequenceProteinA streptavidin fusion protein 39Met Lys Gln Gln Lys Arg Leu Tyr Ala Arg Leu Leu Thr Leu Leu Phe1 5 10 15Ala Leu Ile Phe Leu Leu Pro His Ser Ala Ala Ala Ala Asp Pro Ser 20 25 30Lys Asp Ser Lys Ala Gln Val Ser Ala Ala Glu Ala Gly Ile Thr Gly 35 40 45Thr Trp Tyr Asn Gln Leu Gly Ser Thr Phe Ile Val Thr Ala Gly Ala 50 55 60Asp Gly Ala Leu Thr Gly Thr Tyr Glu Ser Ala Val Gly Asn Ala Glu65 70 75 80Ser Arg Tyr Val Leu Thr Gly Arg Tyr Asp Ser Ala Pro Ala Thr Asp 85 90 95Gly Ser Gly Thr Ala Leu

Gly Trp Thr Val Ala Trp Lys Asn Asn Tyr 100 105 110Arg Asn Ala His Ser Ala Thr Thr Trp Ser Gly Gln Tyr Val Gly Gly 115 120 125Ala Glu Ala Arg Ile Asn Thr Gln Trp Leu Leu Thr Ser Gly Thr Thr 130 135 140Glu Ala Asn Ala Trp Lys Ser Thr Leu Val Gly His Asp Thr Phe Thr145 150 155 160Lys Val Lys Pro Ser Ala Ala Ser Ile Asp Ala Ala Lys Lys Ala Gly 165 170 175Val Asn Asn Gly Asn Pro Leu Asp Ala Val Gln Gln Ser Thr Leu Leu 180 185 190Ile Ser Gly Gly Val Thr Pro Ala Ala Asn Ala Ala Gln His Asp Glu 195 200 205Ala Gln Gln Asn Ala Phe Tyr Gln Val Leu Asn Met Pro Asn Leu Asn 210 215 220Ala Asp Gln Arg Asn Gly Phe Ile Gln Ser Leu Lys Asp Asp Pro Ser225 230 235 240Gln Ser Ala Asn Val Leu Gly Glu Ala Gln Lys Leu Asn Asp Ser Gln 245 250 255Ala Pro Lys Ala Asp Ala Gln Gln Asn Asn Phe Asn Lys Asp Gln Gln 260 265 270Ser Ala Phe Tyr Glu Ile Leu Asn Met Pro Asn Leu Asn Glu Ala Gln 275 280 285Arg Asn Gly Phe Ile Gln Ser Leu Lys Asp Asp Pro Ser Gln Ser Thr 290 295 300Asn Val Leu Gly Glu Ala Lys Lys Leu Asn Glu Ser Gln Ala Pro Lys305 310 315 320Ala Asp Asn Asn Phe Asn Lys Glu Gln Gln Asn Ala Phe Tyr Glu Ile 325 330 335Leu Asn Met Pro Asn Leu Asn Glu Glu Gln Arg Asn Gly Phe Ile Gln 340 345 350Ser Leu

Claims

1-18. (canceled)

19. A process for purification of a target biomolecule, comprising the steps: (a) contacting (i) a target biomolecule, (ii) a dual affinity polypeptide, and (iii) a solid support comprising a catching ligand or dual affinity polypeptide binding site, wherein the ratio between the equilibrium dissociation constants of the dual affinity polypeptide, [K_D,t/K_D,s], is at least 10.sup.0 at standard conditions; and (b) recovering the target biomolecule by elution, wherein the target affinity polypeptide and the dual affinity polypeptide are contacted in solution before the mixture is contacting the solid support comprising a catching ligand or dual affinity polypeptide.

20. The process according to claim 19, wherein the solid support is selected from the group comprising solid phase matrices and particles.

21. The process according to claim 19, wherein the dual affinity polypeptide has an equilibrium dissociation constant, K_D,t towards the target biomolecule in the range from 10.sup.-2 to 10.sup.-13 M, more particularly from 10.sup.-4 to 10.sup.-13 M, preferably in the range from 10.sup.-6 to 10.sup.-13 M and an equilibrium dissociation constant, K_D,s towards the catching ligand in the range from 10.sup.-9 to 10.sup.-16 M, preferably in the range from 10.sup.-11 to 10.sup.-16 M.

22. The process according to claim 19, wherein the ratio between the equilibrium dissociation constants of the dual affinity polypeptide, [K_D,t/K_D,s], is at least 10.sup.1, more particularly at least 10.sup.2, more particularly 10.sup.3, and even more particularly at least 10.sup.4.

23. The process according to claim 19, wherein elution of the target is accomplished by changing either of pH, ionic strength, or content of chaotropic ions in solution, or any combinations thereof.

24. The process according to claim 19, wherein the dual affinity polypeptide is a fusion polypeptide, preferably selected from the group consisting of protein A, antibodies, antibody fragments, protein A fragments, protein A derived IgG binding domains, lipocalins, lectins.

25. The process according to claim 19, wherein the ligand binding part of the dual affinity polypeptide is selected from the group consisting of avidin, streptavidin, neutravidin, steroid receptor, antibody, antibody fragment, lipocalins, lectins, amyloglucosidase, cellulose binding domains.

26. The process according to claim 24, wherein the antibody is selected from the group consisting of llama and camel antibodies.

27. The process according to claim 24, wherein the fusion polypeptide is made by fusion of at least one IgG binding domain of protein A or protein A derived IgG binding domain and at least one biotin binding domain of avidin, streptavidin, or neutravidin.

28. The process according to claim 19, wherein the ligand is selected from the group consisting of biotin, acarbose, steroids, hapten, epitope-peptides, dyes, and enzyme inhibitors.

29. The process according to claim 27, wherein the catching ligand attached to the solid support is biotin and the target biomolecule is IgG.

30. The process according to claim 19, wherein the solid support is a solid phase matrix, preferably selected from the group consisting of agar-agar, agaroses, celluloses, cellulose ethers, carboxymethyl cellulose, polyamides, polyvinylalcohols, silicas, and controlled pore glasses.

31. The process according to claim 24, wherein the fusion polypeptide is produced as a recombinant polypeptide in a recombinant host cell.

32. The process according to claim 31, wherein the fusion polypeptide and the target biomolecule is expressed in the same type of host cell.

33. The process according to claim 31, wherein the host cell is selected from the group consisting bacterial cells, fungal cells, mammalian cells, plant cells, and insect cells.

34. The process according to claim 19, wherein the dual affinity polypeptide is chemically fused.

35. A process for purification of a target biomolecule, comprising the steps: (a) contacting (i) a target polypeptide, (ii) a dual affinity polypeptide, and (iii) a solid support comprising a catching ligand, wherein the dual affinity polypeptide has an equilibrium dissociation constant, K_D,t towards the target biomolecule in the range from 10.sup.-2 to 10.sup.-13 M, preferably from 10.sup.-4 to 10.sup.-13 M, more preferred from 10.sup.-6 to 10.sup.-13 M at standard conditions, and wherein binding of the dual affinity polypeptide to the catching ligand on the solid support is provided by cleavage of a para-substituted benzyl guanine resulting in a thioether bond; and (b) recovering the target biomolecule by elution, where the target polypeptide and the dual affinity polypeptide are contacted in solution before the mixture is contacting the solid support comprising a catching ligand.