化合物I在细胞P450的异构体之间是否有显著的差异?
Richard Lonsdale1, Julianna Oláh, 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
|August 26, 2011
概括
细胞染色体P450 (CYP) 化合物I电子结构的差异不太可能解释人类异形活性变化. 基质的存在稍微降低了整个CYP异型的化合物I稳定性.
科学领域:
- 生物化学 生物化学
- 计算化学计算化学
- 酶学 是一种酶学.
背景情况:
- 细胞染色体P450 (CYP) 酶在药物开发中至关重要.
- 假设CYP异型反应性的差异源于I化合物电子结构的变化.
- 目前的模型通常假定所有CYP异构体中均的化合物I.
研究的目的:
- 开发一种方法来计算CYP化合物I的电子结构和Fe-O键度.
- 为了研究化合物I在人类和细菌CYP异型体中的电子结构.
- 评估化合物I电子结构在CYP异形活性差异中的作用.
主要方法:
- 采用分子动力学模拟来捕捉形状灵活性.
- 使用密度函数理论 (B3LYP) 与QM/MM进行结构优化.
- 计算电子结构并估计化合物I的Fe-O键度.
主要成果:
- 在人类CYP异型中观察到的化合物I的电子结构差异是最小的.
- 单个人类异构体内的变异比异构体之间的差异要大.
- 在人类CYP和P450之间发现了显著的电子结构差异,与结环境有关.
- 基质存在降低了化合物I Fe-O键度,表明稳定性降低.
结论:
- 化合物I电子结构的差异不太可能是人类CYP异形活性变化的主要驱动因素.
- P450中的独特电子结构可能与其特定的活性站点环境有关.
- 化合物I在基质的存在下看起来不太稳定,可能是由于水的移位.
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