氧化酶辅因子的过氧形式的活性. 一个DFT调查调查
Giuseppe Zampella1, Piercarlo Fantucci, Vincent L Pecoraro
1Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, 20126 Milan, Italy.
Journal of the American Chemical Society
|January 20, 2005
概括
密度函数理论揭示了质子化激活瓦氧化酶 (VHPO) 氧复合物. 无质子氧原子促进了氧转移,而Lys353模仿了质子激活.
科学领域:
- 生物化学 生物化学
- 计算化学计算化学
- 酶的机制 酶的机制
背景情况:
- 瓦纳氧化酶 (VHPO) 是一种利用氧-瓦纳辅因子的酶.
- 了解辅助因子的反应性是阐明VHPO催化机制的关键.
研究的目的:
- 研究VHPO过氧复合物的结构,电子和反应性质.
- 检查质子状态和微环境对辅因子反应性的影响.
主要方法:
- 使用密度函数理论 (DFT) 的计算.
- 分析的重点是过氧-复合体模型.
主要成果:
- 质子化显著激活氧-复合体,与实验结果一致.
- 氧转移步骤涉及一种可访问的,无质子化的轴性过氧氧.
- 发现Lys353可能模仿过氧辅因子的质子激活.
结论:
- 质子化对于激活VHPO Peroxo辅因子至关重要.
- 酶的活性部位有助于基质进入反应性过氧氧.
- 像Lys353这样的氨基酸残留物可以在调节VHPO活性方面发挥作用.
相关概念视频
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Cofactors can be metallic ions or organic molecules called coenzymes. These types of helper...
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The extended Debye-Hückel equation indicates that the activity coefficient of an ion in an aqueous solution at 25°C depends on three partially interdependent properties: the ionic strength of the solution, the charge of the ion, and the ion size.
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