金属离子Zn^(2+)对精氨酸酶抑制作用的研究  

Investigation on the inhibition against arginase catalyzed reaction by Zn^(2+)

作　　者：史竞艳[1] 王志勇[2] 刘欲文[2] 汪存信[2] 

机构地区：[1]武汉生物工程学院化学与环境工程系,湖北武汉430415 [2]武汉大学化学与分子科学学院,湖北武汉43072

出　　处：《化学研究与应用》2012年第3期370-374,共5页Chemical Research and Application

基　　金：湖北省教育厅科研资助基金(B20094006)资助;武汉市教育局科研资助基金(2008K016)资助

摘　　要：在37℃,pH=9.4,40 mmol.L-1的巴比妥钠-盐酸缓冲体系中,利用微量热法研究了金属离子Zn2+对牛肝精氨酸酶催化L-精氨酸水解反应的影响。实验表明,Zn2+对精氨酸酶催化反应存在着明显抑制作用,其抑制类型为竞争性可逆抑制,并求得抑制常数KI为6.85×10-7mol.L-1。根据其抑制类型和离子半径,推测Zn2+对精氨酸酶的抑制主要是夺取Mn2+的位置,从而使酶失活。The influence of Zn2＋ on arginase catalyzed reaction was studied by microcalorimetry at 37℃,pH=9.4,40 mmol·L-1 sodium barbiturate-hydrochloric acid buffer solution.The result indicated that Zn2＋ has remarkable inhibition effect on the catalytic activity of arginase and the inhibitory type belongs to the reversible competitive inhibition with the inhibition constants of 6.85×10-7 mol·L-1.According to the inhibition type and ion radius,we suggest that the reason for inhibition is the competition of Zn2＋on the active site of arginase and thus inhibits the reaction activity of arginase.

关 键 词：精氨酸酶 锌 竞争性可逆抑制 微量热法 

分 类 号：O614.2[理学—无机化学]