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对L-proline脱酶的化物和质子转移机制的计算见解
1Chemistry Department and Applied Material Chemistry Center (AMCC), Khalifa University, Abu Dhabi, UAE.
PloS one
|November 15, 2023
概括
通过一个逐步的机制,L-proline脱酶 (ProDH) 催化L-proline氧化. 计算研究证实了初始deprotonation,其次是限制速度的化物转移到FAD.
科学领域:
- 生物化学 生化学
- 酶学 是一种酶学.
- 计算化学的计算化学
背景情况:
- 氨酸脱酶 (ProDH) 是一种关键的氨酸依赖酶.
- 它将L-proline氧化为 (S) -1-pyrroline-5-carboxylate. 它可以将L-proline氧化为 (S) -1-pyrroline-5-carboxylate. 它可以将L-proline氧化为 (S) -1-pyrroline-5-carboxylate.
- 实验数据表明一个阶段性质子和化物转移机制.
研究的目的:
- 通过计算来研究 ProDH 减少性半反应的机制.
- 为了阐明L-proline的氧化到iminoproline的过程.
- 为了澄清酶反应中的速度限制步骤.
主要方法:
- 计算力学研究.计算力学研究.
- 使用了ONIOM (我们自己的N层集成分子轨道和分子力学) 方法.
- 分析了质子和化物转移步骤.
主要成果:
- 计算支持一个逐步的机制:L-proline的初始快速去质子化到Lys.
- 随后从L-proline到FAD的化物离子转移具有更高的激活屏障.
- 在酶产品复合体中观察到减少的FAD和伊米诺普罗林之间的强烈相互作用.
结论:
- 计算结果验证了ProDH的拟议阶段性机制.
- 证实化物转移步骤具有显著的激活障碍.
- 酶-产物复合相互作用可能解释氧化半反应中的速度限制步骤.
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