Patent ID: 7785859

Claim:
An isolated host cell comprising: (i) a nucleic acid sequence encoding a variant of a wild type coat protein of a bacteriophage, (aa) wherein said nucleic acid sequence encoding said variant comprises a nucleic acid sequence encoding at least one part of said wild type coat protein of a bacteriophage, wherein said at least one part comprises at least that part which causes or allows the incorporation of said coat protein into the phage coat, and (ab) wherein said variant comprises a cysteine residue, wherein said cysteine residue is present at, or in the vicinity of, the C- or the N-terminus of said at least one part of said wild type coat protein, (ii) one or more nucleic acid sequences encoding a (poly)peptide/protein comprising a cysteine residue, wherein upon expression of said nucleic acid sequence encoding said variant of a wild type coat protein and said one or more nucleic acid sequences encoding a (poly)peptide/protein comprising a cysteine residue, attachment of said variant of a wild type coat protein and said (poly)peptide/protein occurs by formation of a disulfide bond between said cysteine residue in said variant of a wild type coat protein and said cysteine residue comprised in said (poly)peptide/protein, wherein said nucleic acid sequence encoding a variant of a wild type coat protein does not encode an interaction domain for interaction with a second domain present in said (poly)peptide/protein, and wherein the expression product of said nucleic acid sequence encoding said variant of a wild type coat protein and the expression product or products of any of said one or more nucleic acid sequences encoding a (poly)peptide/protein do not form a genetic fusion protein.