Isolation and characterization of an arginine ester hydrolase from Bothrops jararacussu venom which induces contractions of the isolated rat uterus

The isolation and partial characterization of a serine protease with arginine ester hydrolase activity from Bothrops jararacussu snake venom are described. The purification procedure consisted of a gel filtration of the crude venom on Sephadex G-75 followed by an ion-exchange chromatography of the active fraction on DEAE-cellulose and a rechromatography on Bio-Rex 70 resin. The esterase fraction (DI-III), Mr=25,000 by SDS-PAGE, showed proteolytic activity on fibrinogen and casein. After 2hr incubation, the Aα and Bβ chains of fibrinogen were intensely hydrolysed, while the γ, chain kept apparentely intact, even after 20hr of incubation. In spite of that, DI-III did not clot fibrinogen. DI-III induced edema in the rat paw. Although unable to release bradykinin, it induced contractions of the isolated rat uterus. DI-III did not catalyse the hydrolysis of bradykinin. Its arginine ester hydrolase activity was completely inhibited by diisopropyl fluorophosphate after 1 hr incubation, but not by phenylmethylsulfonyl fluoride under the same conditions.