摘要
本文报道从竹叶青蛇毒中纯化的两个凝血酶样酶(组分Ⅰ和组分Ⅱ)的酶学性质研究。结果表明二者在体外都能使人纤维蛋白原转变为纤维蛋白,具有精氨酸酯酶活性,都能水解凝血酶专一性底物。纤维蛋白平板法证明组分Ⅰ具有激活纤溶作用;组分Ⅱ同时具有激活纤溶和直接纤溶作用;组分Ⅰ和组分Ⅱ能缓慢降解纤维蛋白原的α链,随着作用时间延长,组分Ⅰ还能进一步部分降解纤维蛋白原的β链,活性中心探讨表明,组分Ⅰ的活性中心由丝氨酸蛋白酶部位和糖基部位组成。组分Ⅰ水解BAEE的最适温度为50℃,最适pH为8.6。
In this paper, enzymic properties of two thrombin-like enzymes (principle I and principle II) was reported. The results showed that principle I and principle II could convert human fibrinogcn into fibrin, both had arginine esterase activity and could hydrolyze Bz-Phc-Val-Arg-PNA which was special substrate of thrombin. Principle I and principle II had an activated fibrinolysis and principle II also had a direct fibrinolysis as showed by plate method of fibrin, principle I and principle II could slowly degrade the a chain of fibrinogen and principle I also could further degrade the β chain of fibrinogen. The active center of principle I is a serinc protease and has a glycosyl site. The optimal temperature was 50℃ and the optimal pH was 8.6 for principle I to hydrolyze BAEE.
关键词
竹叶青蛇
凝血酶样酶
酶学性质
Thrombin-like enzyme, Special substrate of thrombin, Active center, Degradation of fibrinogen
