Patent ID: 7498148

Claim:
A method for producing a desired peptide from a polypeptide, comprising: combining the polypeptide and clostripain, wherein the polypeptide comprises Formula (II) (Xaa 3 -Peptide 1 -Xaa 1 -Xaa 2 ) n -Xaa 3 -Peptide 1 -Xaa 1 -Xaa 2 (II); the desired peptide comprises Xaa 3 -Peptide 1 -Xaa 1 -Xaa 2 ; Peptide 1 is any amino acid sequence other than Xaa 1 -Xaa 2 ; n is an integer ranging from 0 to 50; Xaa 1 is aspartic acid, glycine, proline or glutamic acid; Xaa 2 is arginine; and Xaa 3 is not an acidic amino acid; wherein the peptide bond between Xaa 2 and the amino acid on the C-terminal side of Xaa 2 is cleaved; and wherein the cleavage occurs selectively over cleavage at other arginine or lysine residues within the polypeptide.