牛肝锌离子螯合酶粗酶液的特性

摘要

以牛肝脏中锌离子螯合酶粗酶液为研究对象,对其特性进行研究。结果表明：锌离子螯合酶的最适pH值为6.0,最适温度为60℃;最初的底物浓度与相对酶活力呈正相关;该酶能催化利用含有卟啉环的物质,对原卟啉二钠催化效果尤其明显;单一的激活剂VC、三磷酸腺苷（ATP）对锌离子螯合酶有激活作用,相对酶活力随其添加浓度的增加而升高;金属离子（Fe2＋、Mg2＋）对锌离子螯合酶有抑制作用。%Crude zinc chelatase extract prepared from bovine liver and characterized in the present study.The optimal reaction pH and temperature for this enzyme were 6.0 and 60 ℃,respectively,and initial substrate concentration was positively correlated with enzyme activity.This enzyme could catalyze substances with porphyrin ring,especially protoporphyrin disodium.Several activators such as ascorbic acid and ATP could activate its activity in a concentrationdependent manner,whereas Fe2+and Mg2+had inhibitory effect on its activity.