在可溶性环氧化酸酶中对酸酶活性进行计算研究:通过水桥介导的质子穿机提供高效率
Marco De Vivo1, Bernd Ensing, Michael L Klein
1Center for Molecular Modeling, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104-6323, USA. mdevivo@cmm.upenn.edu
Journal of the American Chemical Society
|August 11, 2005
概括
溶性环氧化酶 (sEH) 呈现出新型的酸酶活性,揭示了药物开发的新目标. 计算研究阐明了一种协调的反应机制,其中包括一个对于催化作用至关重要的水桥.
科学领域:
- 生物化学 生物化学
- 酶学 是一种酶学.
- 药物发现 药物发现 药物发现
背景情况:
- 可溶性环氧化酶 (sEH) 是一种双功能酶.
- 在sEH的N端域中发现了一种新型的酸酶活性.
- 这种活动为脂肪酸代谢中的药物向开辟了新的途径.
研究的目的:
- 为了研究在sEH催化过程中酶中间体形成的反应机制.
- 了解水桥在催化过程中的作用.
- 为药物开发提供洞察力,针对sEH活动.
主要方法:
- 经典分子动力学 (MD) 模拟.
- 混合动力汽车-帕里内洛量子力学/分子力学 (QM/MM) 计算.
- 催化路径的自由能量计算.
主要成果:
- 一个协调的多事件反应机制得到了支持.
- 关键步骤包括解离性直线核替代和双质子转移.
- 水桥促进了高效的质子穿,加速了催化.
- 计算的自由能量障碍 (19 kcal/mol) 与实验数据非常一致.
结论:
- 这项研究阐明了sEH新型酸酶活性的详细催化机制.
- 这些发现强调了水桥在质子转移和催化中的重要性.
- 这项研究为设计sEH抑制剂提供了机制基础.
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