卤过氧化物酶催化的“热力学”机制

'Thermodynamic' mechanism of catalysis by haloperoxidases.

作者信息

Shevelkova A N, Sal'nikov Y I, Kuz'mina N L, Ryabov A D

机构信息

Department of Chemistry, M.V. Lomonosov Moscow State University, Russia.

出版信息

FEBS Lett. 1996 Apr 1;383(3):259-63. doi: 10.1016/0014-5793(96)00209-8.

DOI:10.1016/0014-5793(96)00209-8

PMID:8925909

Abstract

A novel 'thermodynamic' mechanistic rationale of haloperoxidase catalysis is based on the following two assumptions: (i) the role of enzyme consists only in the rapid equilibration between the halogen-containing species originating from halide and hydrogen peroxide; (ii) the interaction between the enzyme and organic substrate is kinetically insignificant and halogenation occurs as a result of the electrophilic attack of the active brominating (Br3-, Br2 and HBrO) or chlorinating (HCIO) species at monochlorodimedon indicative of a higher chloride 'specificity' of chloroperoxidase from C. fumago.

摘要

一种新颖的卤过氧化物酶催化的“热力学”机制原理基于以下两个假设：(i) 酶的作用仅在于源自卤化物和过氧化氢的含卤素物种之间的快速平衡；(ii) 酶与有机底物之间的相互作用在动力学上不显著，卤化反应是由于活性溴化（Br3-、Br2和HBrO）或氯化（HClO）物种对一氯二甲基苯醌的亲电攻击而发生的，这表明来自烟曲霉的氯过氧化物酶具有更高的氯“特异性”。