Partial Purification and Characterization of Two Peptide Hydrolases from Pea Seeds

Abstract

Two peptide hydrolases were found in pea seeds (Pisum sativum cv. ''Greenfeast'') and extensively purified by ion exchange chromatography using benzoyl-DL-arginine-p-nitroanilide as substrate. The enzymes which both had MW of 65,00 can be separated by anion exchange chromatography but were otherwise virtually identical in the properties tested. They did not hydrolyze several common protease substrates but readily hydrolyzed small peptides containing basic amino acids on the carboxyl side of these residues. They were completely inhibited by diisopropylfluorophosphate and were inhibited to varying extents by thiol reagents.