高等学校化学学报 ›› 1997, Vol. 18 ›› Issue (5): 786.

• 论文 • 上一篇    下一篇

微量热法研究漆酶和3,4,5-三羟基苯甲酸的反应

望天志1, 吴鼎泉1, 万洪文2, 屈松生1, 杜予民1   

  1. 1. 武汉大学化学系, 武汉, 430072;
    2. 华中师范大学化学系, 武汉, 430070
  • 收稿日期:1996-05-27 出版日期:1997-05-24 发布日期:1997-05-24
  • 通讯作者: 吴鼎泉.
  • 作者简介:望天志, 男, 28岁, 博士研究生.
  • 基金资助:

    国家自然科学基金

Studies on the Reaction Between Laccase and 3,4,5-Trihydroxybenzoic Acid by Microcalorimetry

WANG Tian-Zhi1, WU Ding-Quan1, WAN Hong-Went2, QU Song-Sheng1, DU Yu-Min1   

  1. 1. Department of Chemistry, Wuhan University, Wuhan, 430072;
    2. Department of Chemistry, Central China Normal Universityt, Wuhan, 430070
  • Received:1996-05-27 Online:1997-05-24 Published:1997-05-24

摘要: 用LKB-2107型微量热系统,在不同的温度(pH=7.4)条件下,测定了3,4,5-三羟基苯甲酸与漆酶反应的摩尔反应烙、米氏常数、反应速率常数、漆酶的活性并计算了结合能、活化自由能、活化能和活化烟等.在此基础上,应用过渡态理论,从能量变化的角度,对其催化过程进行了分析.由活化摘(△ST<0)得出酶-底物过渡态的结构较酶-底物复合物更为有序的结论.

关键词: 漆酶, 微量热法, 过渡态, 3, 4, 5-三羟基苯甲酸

Abstract: The reactions between laccase and 3,4,5-trihydroxybenzoic acid have been studied by LKB-2107 batch microcalorimetry system at different temperatures and pH = 7.4.The rnolar reaction enthalpy (ΔrHm), the Michaelis constant (Km), the rate constant (k2), the laccase activity (EA), the binding energy (ΔG0), the activation Gibbs free energy (ΔGT),the actlvation energy(Ea) and the activation entropy (ΔST) have been determined.The results have been discussed from changes in free energy by using the transition state theory.The activation entropy (ΔST < 0) indicated that enzyme-substrate/transition structure is bound more orderly than enzyme-substrate complex.

Key words: Laccase, Microcalorimetry, Transition state,3,4,5-Trihydroxybenzoic acid

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