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Defining Substrate Specificities for Lipase and Phospholipase Candidates
Published on: November 23, 2016
基质溶解如何有助于subtilisin对二次醇的酶选择性
Christopher K Savile1, Romas J Kazlauskas
1Department of Chemistry, McGill University, 801 Sherbrooke Street West, Montréal, Québec, Canada, H3A 2K6.
Journal of the American Chemical Society
|September 1, 2005
概括
亚提利西尼是什么?亚提利西尼是什么?
科学领域:
- 生物催化和酶工程 生物催化和酶工程
- 有机化学 有机化学
- 蛋白质结构和功能 蛋白质结构和功能
背景情况:
- 在二次酒精反应中预测细素的酶选择活性的既定规则假定替代剂有两个活性位点口袋.
- 实验数据,包括X射线晶体学,与这一规则相矛盾,仅显示一个适合类大小组的口袋 (S1').
- 现有的规则经常错误地预测水性环境中的反选择性.
研究的目的:
- 解决在预测Subtilisin对二次醇的反选择性方面的矛盾.
- 为了完善管理生物催化剂中的酶基质相互作用的经验规则.
- 阐明替代物性质在酶催化酶选择性反应中的作用.
主要方法:
- 细素的X射线结晶学分析活性部位结构.
- 用水溶液中的一系列二次醇进行酶动力学研究.
- 异构选择性和替代剂疏水性之间的相关性分析 (log P/P0).
主要成果:
- 苏比利辛的活性部位 (S1'口袋) 只容纳了一种二次醇的替代剂.
- 另一种替代剂暴露于水溶剂并被水溶剂溶解.
- 乙选择性与两种替代剂之间的疏水性差异呈现出线性相关性.
结论:
- 精制规则认为,亚提利辛结合一个替代剂,留下另一个在溶剂中.
- 替代剂的疏水性差异是决定水中的酶选择性的一个关键因素.
- 这一发现为预测酶催化酶选择性反应提供了更准确的模型.
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