对降酶对化和碳基组的选择性差异的理论分析
Ru-De Lin1, Xiu Xing1, Yuan Yu1
1Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, P. R. China.
Journal of chemical information and modeling
|March 27, 2024
概括
乳酸菌酒精脱酶和克里西奥细菌sp. 由于活性口袋的结构差异,降酶表现出明显的化学选择性. 关键残留物稳定基板,使选择性减少成为可能,并提供机械洞察力.
科学领域:
- 生物催化剂是一种生物催化剂.
- 酶工程是什么? 酶工程是什么?
- 结构生物学 结构生物学
背景情况:
- 酒精脱酶 (ADH) 和缩酶 (KRED) 是重要的生物催化剂.
- 酶选择性对于合成奇拉化合物至关重要.
- 了解酶活性位点可以解释基质特异性.
研究的目的:
- 研究Lactobacillus kefir酒精脱酶 (LkADH) 和Chryseobacterium sp.之间不同化学选择性的结构基础. CA49 基因减少酶 (ChKRED12).
- 确定负责基质稳定和选择性减少的关键残留物和相互作用.
- 阐明 LkADH 的 enantioselectivity 机制.
主要方法:
- 分子动力学 (MD) 模拟来分析酶基质相互作用.
- 量子化学计算以确定反应机制和能量.
- 活性部位结构和关键氨基酸残留物的比较分析.
主要成果:
- LkADH和ChKRED12具有独特的活性口袋结构,决定了化学选择性.
- LkADH可以选择性地将碳酸降低到R-酒精,而ChKRED12可以选择性地降低化碳酸.
- 特定残留物 (LkADH中的N89,N113,E144;ChKRED中的Q151,D190) 对于通过静电和范德瓦尔斯力结合基质至关重要.
- 通过量子化学方法阐明LkADH的酶选择性机制.
结论:
- 活动部位架构是LkADH和ChKRED中化学选择性的主要决定因素12.
- 已识别的残留物在酶催化和基质特异性中起着至关重要的作用.
- 实现了对生物催化选择性的详细机制理解,有助于酶设计.
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