Kallikrein-like enzyme from the venom of Agkistrodon p. piscivorus.

1. A kallikrein-like enzyme was isolated from Agkistrodon p. piscivorus venom by Sephadex G-100, DEAE-Sephacel and S-Sepharose column chromatographies. 2. A kallikrein-like enzyme was shown to be homogeneous as demonstrated by a single band on acrylamide gel electrophoresis, sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunodiffusion. 3. Its molecular weight is approx. 29,000 with an isoelectric point of 7.8. 4. A kallikrein-like enzyme is able to cleave a kininogen analog to release bradykinin, and the B beta chain of fibrinogen. These proteolytic and tosyl-L-arginine methyl ester hydrolytic activities were inhibited by diisopropyl fluorophosphate, suggesting that the serine hydroxyl group is involved in enzymatic activities.