酸酶的FeMoco添加到FeMoco的第一个合的电子和质子的结合模式
Timothy Lovell1, Jian Li, David A Case
1The Scripps Research Institute, La Jolla California 92037, USA.
Journal of the American Chemical Society
|April 25, 2002
概括
研究人员模拟了酶活性部位,发现了受青的铁化物中间体. 这可能是从铁-辅因子中释放二的第一步.
科学领域:
- 生物化学和计算化学.
- 酶的机制 酶的机制
- 固化的研究研究 固的研究
背景情况:
- 酶对于将大气中的转化为氨至关重要.
- 铁辅因子 (FeMoco) 是酶的催化中心.
- 了解FeMoco的反应机制是改善固化的关键.
研究的目的:
- 为了建模FeMoco活性位点的一个电子减少和质子化状态.
- 为了确定FeMoco中最稳定的质子位点.
- 为了阐明二释放的初始步骤.
主要方法:
- 利用了结合的断对称密度函数理论 (DFT) 和静电学方法.
- 在FeMoco的Fe,Mo,S,N和O原子中检查了各种潜在的质子化位点.
- 计算了不同质子状态的能量有利性.
主要成果:
- 确定了一个新的,不对称地位于六个铁位点形成的中央腔体中的化质子.
- 这种铁化物中间体是计算上最受能量青的状态.
- 这种中间体的形成被认为是二释放的潜在初始步骤.
结论:
- 计算的铁化物中间体为FeMoco机制提供了洞察力.
- 这一发现表明,二释放的途径独立于二结合.
- 进一步的研究可以在生理条件下探索这种中间体.
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