ATP结合和阿斯巴酸质子增强植物加密染色体中的光诱导电子转移
Fabien Cailliez1, Pavel Müller, Michaël Gallois
1Laboratoire de Chimie Physique, UMR 8000, Université Paris-Sud and CNRS , Orsay F-91405, France.
Journal of the American Chemical Society
|August 27, 2014
概括
ATP 结合和 pH 显著影响加密染色体.
科学领域:
- 生物化学 生物化学
- 摄影生物学 摄影生物学
- 分子生物学分子生物学
背景情况:
- 加密染色体是植物和动物中的蓝光受体.
- 它们的功能涉及黄蛋白FAD辅因子.
- 光引起的FAD减少导致了极端状态.
研究的目的:
- 分析ATP和pH对加密色光降解的影响的分子机制.
- 研究ATP结合和D396质子化状态如何调节FADH°形成.
主要方法:
- 组合的经典分子动力学 (MD) 模拟.
- 时间依赖密度函数理论 (TD-DFT) 的计算.
主要成果:
- ATP和质子化D396保持密切的FAD-W400接触,增强电子转移 (ET).
- D396脱质和ATP的缺失增加了FAD-W400距离,降低了ET速率.
- 在这些条件下,来自FAD的腺因部分的ET成为一种竞争性途径.
结论:
- 对FAD光降解的ATP和pH效应起源于最初的步骤.
- ATP 结合和 D396 质子化状态决定了异氧环的主要放松路径.
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