高等学校化学学报 ›› 1995, Vol. 16 ›› Issue (5): 744.

• 论文 • 上一篇    下一篇

微量热法研究PCMB对精氨酸酶的抑制作用

梁毅1, 汪存信1, 吴鼎泉1, 屈松生1, 邹国林2   

  1. 1. 武汉大学化学系, 武汉, 430072;
    2. 武汉大学生命科学院, 武汉, 430072
  • 收稿日期:1994-05-27 修回日期:1994-12-03 出版日期:1995-05-24 发布日期:1995-05-24
  • 通讯作者: 梁毅,男,30岁,硕士,讲师,现在武汉化工学院精细化工系工作(邮编:430074).
  • 作者简介:梁毅,男,30岁.硕士,讲师,现在武汉化工学院精细化工系工作(邮编:430074).
  • 基金资助:

    国家自然科学基金

Studies on the Inhibiting Action of PCMB to Arginase Using Microcalorimetry

LIANG Yi1, WANG Cun-Xin1, WU Ding-Quan1, QU Song-Sheng1, ZOU Guo-Lin2   

  1. 1. Department of Chemistry, Wuhan University, Wuhan, 430072;
    2. College of Life Science, Wuhan University, Wuhan, 430072
  • Received:1994-05-27 Revised:1994-12-03 Online:1995-05-24 Published:1995-05-24

摘要: 利用微量热法研究了对-氯汞苯甲酸(PCMB)对精氨酸的酶促水解反应的抑制作用,确定它属于竞争性不可逆抑制剂,在298.15K和pH为9.4时PCMB与精氨酸酶作用的二级速度常数k+0=92.17L/(mol·s).同时用PCMB作为修饰剂探讨了精氨酸酶的活性中心性质,推测该水解酶至多含有3个与酶活性有关的半胱氨酸残基,但这些残基不属于精氨酸酶的活性中心。

关键词: 微量热法, 精氨酸酶, 对-氯汞苯甲酸, 不可逆抑制

Abstract: Microcalorimetry was used to study the inhibiting action of p-chloromer curibenzoic acid(PCMB)to L-arginine hydrolysis with arginase, PCMB was determined as a competitive irreversible inhibitor and the second-order rate constant of the reaction between PCMB and arginase was k+0=92. 17 L/(mol· s)at 298.15 Kand pH 9.4.The properties of the active site of arginase were investigated by using PCMB as a modifying agent.The results of chemical modification reveal that arginase contains 3 reactive cysteinyl residues at most but these residues do not belong to the active site of arginase. The modification of 3 cysteinyl residues by PCMBled to~50% inhibition of arginase activity.

Key words: Microcalorimetry, Arginase, p-Chloromercuribenzoic acid, Irreversible inhibi Tion

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