在酶催化中寻找自动路径战略:LMCpfCC的案例研究
1School of Chemistry, Sun Yat-Sen University, Guangzhou, 510006, China.
概括
离散路径采样 (DPS) 为酶催化研究提供了一种不那么干预的方法. 这种方法确定了在Listeria monocytogenes coproporphyrin ferrochelatase中Fe (II) 插入的更有利途径.
科学领域:
- 生物化学 生物化学
- 计算化学的计算化学
- 酶学 是一种酶学.
背景情况:
- 酶反应机制是复杂的,很难通过计算来研究.
- 人工干预可以阻碍对这些机制的准确探索.
研究的目的:
- 引入和验证离散路径采样 (DPS) 作为探索酶反应路径的自动策略.
- 调查Listeria monocytogenes配氨酸铁甲酸酶 (LmCpfC) 在催化Fe(II) 插入到配氨酸III (cpIII) 中的详细机制.
主要方法:
- 在酶催化中用于自动路径搜索的雇佣离散路径采样 (DPS).
- 从Tyr12和Glu263,LmCpfC的His182两侧向cpIII插入Fe (II) 的研究.
- 将DPS结果与潜在能量表面扫描和推动弹性带方法进行比较.
主要成果:
- DPS发现Tyr12侧的Fe (II) 插入在热力学和动力学上是有利的 (ΔH = -42.24 kcal/mol,屏障 = 7.28 kcal/mol).
- 来自Glu263的插入,His182侧的插入不那么有利 (ΔH = +21.88 kcal/mol,屏障 = 34.64 kcal/mol).
- 与其他方法相比,DPS产生了明显较低的能源障碍,计算干预较少.
结论:
- DPS是一种有效的计算策略,可以在减少人工干预的情况下阐明酶反应机制.
- Tyr12侧路径是由LmCpfC催化的Fe(II) 插入的首选路径,与实验观测一致.
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