Patent ID: 8541200

Claim:
A method for the preparation of a polypeptide of interest in authentic form, said method comprising the steps of: (i) providing a fusion protein comprising, from its N-terminal to its C-terminal, (a) a fusion partner, (b) a Granzyme B protease recognition site comprising a Granzyme B protease cleavage site that is cleavable by human Granzyme B protease, and wherein the recognition site comprises an amino acid sequence of the general formula P4 P3 P2 P1 ↓ (SEQ ID NO: 59) wherein P4 is amino acid I or V, P3 is amino acid E, Q or M, P2 is X, where X denotes any amino acid, P1 is amino acid D, and ↓ is said Granzyme B protease cleavage site, and (c) the polypeptide of interest, wherein said cleavage site is adjacent to the polypeptide of interest, and (ii) cleaving the fusion protein with Granzyme B protease at said cleavage site to yield said polypeptide of interest in authentic form.