Patent ID: 8728985

Claim:
A replicable phage vector for the display of a functional, multimeric, interchain disulfide linked protein on the surface of a filamentous phage particle; comprising nucleic acid sequences encoding an inducible promoter and nucleic acid sequences encoding a first polypeptide chain and a second polypeptide chain wherein each chain consists of amino acid residues according to the following formula: N-(a bacterial secretion signal)-(Formula I)-(a phage coat protein)-C wherein N is the N-terminus and C is the C-terminus; wherein the phage coat protein is a phage pIX or pVII protein; wherein Formula I is V1 o -Pep a -Flex n -V2 m -Hinge-CH 2 —CH 3 ; wherein Pep represents a bioactive peptide or polypeptide capable of specifically recognizing a target; wherein Flex is an optional flexible linker polypeptide that provides structural flexibility; wherein V1 and V2 are bracketing sequences; wherein Hinge is at least a portion of an immunoglobulin hinge region selected from the group consisting of: SEQ ID NO: 1-4, SEQ ID NO 1 amino acid residues 11-15, SEQ ID NO 2 amino acid residues 8-12, SEQ ID NO 3 amino acid residues 13-61 and SEQ ID NO 4 amino acid residues 8-12; wherein CH 2 is at least a portion of an immunoglobulin CH 2 constant region; wherein CH 3 is at least a portion of an immunoglobulin CH 3 constant region; wherein m, n and o can be zero or can be an integer between 1 and 10, and a can be an integer from 1 to 10; wherein said encoded Hinge amino acid sequence comprises at least one cysteine residue; wherein a cysteine residue on the first polypeptide chain is capable of becoming oxidatively bonded to a Hinge cysteine residue on the second polypeptide chain; and whereby the cysteine bond so formed is an interchain disulfide of the functional multimeric structure being displayed on the surface of the same filamentous phage particle.