Enzymatic Properties and Biological Activities of A Proteolytic Enzyme (Proteinase A) From The Venom of Agkistrodon Halys Pallas

A proteolytic enzyme from the venom of Agkistrodon halys Pallas has been purified by ion-exchang chromatography and by gel-filtration.This proteolytic enzyme (called proteinase a) can hydrolyze casein.Using casein as the substrate,the optimum pH is about 9.5,the optimum temperature is about 45℃,and Km=1.33×10-5 mol/L.Its activity toward casein was inhibited by EDTA.It did not act on TAME and BAEE.Proteinase a showed fibrinolytic activity in vitro,EDTA and cysteine could inhibite this activity.