从QM/MM建模中获得的人类细胞染色体P450异型中的化合物I的电子结构
Christine M Bathelt1, Jolanta Zurek, Adrian J Mulholland
1Centre for Computational Chemistry, School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS United Kingdom.
Journal of the American Chemical Society
|September 15, 2005
概括
人类P450细胞染色体对于药物代谢至关重要. 它们的化合物I中间体在主要药物代谢异型中显示了类似的电子结构,具有蛋白质构造,而不是电子差异,驱动反应性变化.
科学领域:
- 生物化学 生化学
- 计算化学计算化学
- 药理学 药理学是指药理学的学科.
背景情况:
- 人类P450细胞染色体是药物代谢中必不可少的酶.
- 由化合物I氧化基质是关键的代谢步骤.
- 化合物I的电子结构可能会影响酶的反应性.
研究的目的:
- 描述化合物I的电子和几何结构.
- 研究三个主要的人类细胞染色体P450亚家族 (P450,2C,2B和3A).
- 评估方法和基质存在对化合物I结构的影响.
主要方法:
- 量子力学/分子力学 (QM/MM) 的结合计算.
- B3LYP:CHARMM27 理论水平. 在理论上.
- 在化合物I中分析旋转密度分布.
主要成果:
- 化合物I在研究的人类P450异型中表现出非常相似的电子结构.
- 第三个未配对的电子主要位于氨酸环上.
- 聚乙烯硫的旋转密度的变化主要是由于蛋白质构成,而不是异形差异或基质存在.
- 方法变化 (DFT功能,基础集,QM区域大小) 的影响最小.
结论:
- 化合物I的电子结构在主要的人类药物代谢P450异型中得到保存.
- 蛋白质构成效应,而不是电子差异,是反应性变化的主要来源.
- 观察到的基质选择性差异不太可能通过化合物I的电子变化来解释.
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