催化二和氧化离子孔的计算设计用于水解
Florian Richter1, Rebecca Blomberg, Sagar D Khare
1Department of Biochemistry, University of Washington, Seattle, Washington 98195, USA.
Journal of the American Chemical Society
|August 9, 2012
概括
人工酶的计算设计显示,骨干NH组对于氧离子孔至关重要,提高了催化效率. 然而,在实现高活动和适当的活跃地点形成方面,仍然存在挑战.
科学领域:
- 生物化学 生物化学
- 计算化学计算化学
- 酵素工程是什么意思 酵素工程
背景情况:
- 核性催化加速了水解反应.
- 自然酶利用催化二/三和氧化离子孔来激活基质.
- 解开这些成分在自然进化中的作用是具有挑战性的.
研究的目的:
- 探索对酶活性的最低要求.
- 使用催化二和氧化离子孔计算设计人工催化剂.
- 调查催化动机的独立贡献.
主要方法:
- 人工催化剂的计算设计.
- 使用催化二 (Cys-His) 和设计的氧离子孔.
- 活动现场优化和运动实验.
- 通过晶体学进行结构分析.
主要成果:
- 从骨干NH组设计的氧化离子孔显示出更高的成功率.
- 在不同的脚手架上生成了四个活跃的设计.
- 最活跃的变体实现了400M{-1}s{-1}的催化效率 (k{-cat}/K{-M}).
- 活性部位氨酸的化是有效的,但酶水解是缓慢的.
- 设计的Cys-His二极管在晶体结构中没有正确形成.
结论:
- 脊柱NH基对于在人工化中设计氧离子孔是有效的.
- 实现高催化效率受到缓慢的乙酶中间水解的限制.
- 计算设计在复制自然酶活性部位的真实性方面面临着挑战.
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