The specificity of porcine trypsin

Abstract

During the past several years it has been the custom to use bovine trypsin as the source for tryptic digestion of proteins. This enzyme, although highly specific for arginine and lysine residues, is usually contaminated with chymotrypsin and must be pre-treated with TPCK 2 2 Abbreviations: TPCK, L-(1-tosylamido-2-phenyl)-ethyl-chloromethyl ketone; BAEE, N-benzoyl-L-arginine ethyl ester; ATEE, N-acetyl-L-tyrosine ethyl ester. prior to use in order to avert formation of chymotryptic peptides Kostka and Carpenter 1964; Walsh et al. 1962 Heller and Smith 1965. Furthermore, the autolytic nature of bovine trypsin requires that repeated addition of enzyme be made in order to insure total tryptic digestion. This report deals with the enzymatic specificity of porcine trypsin, a stable proteolytic enzyme which can be obtained essentially chymotrypsin free and which should prove useful as a digestive agent.