Clostripain is a neutral protease secreted by C. histolyticum during the fermentation process. It is a tryptic like enzyme that is measured using the same peptide substrate to measure trypsin activity (N-benzoyl-L-arginine ethyl ester, BAEE). Clostripain is a sulfhydrl enzyme that expresses maximal enzyme activity under reducing conditions (i.e., pre-incubation with 2 mercapatoethanol or other reducing agent). It is reported on a Certificate of Analysis as clostripain or total clostripain activity. Trypsin like activity measures clostripain activity in the absence of reducing agent. It usually represents about 10% of the total clostripain activity.