静电引导的动力学 - - 在乱交的烯合成酶中,忠诚的根源?
Dan Thomas Major1, Michal Weitman
1Department of Chemistry and the Lise Meitner-Minerva Center of Computational Quantum Chemistry, Bar-Ilan University, Ramat-Gan 52900, Israel. majort@biu.ac.il
Journal of the American Chemical Society
|October 30, 2012
概括
烯循环从简单的前体产生多样化的天然产品. 这项研究揭示了基二酸盐合成酶如何指导反应,解释了为什么这些酶有时会产生不必要的副产品.
科学领域:
- 生物化学 生物化学
- 酶学 是一种酶学.
- 计算化学计算化学
背景情况:
- 烯循环酶从有限的线性异oprenoid基质合成超过6万种自然产品.
- 烯循环酶的催化杂交在理解天然产品生物合成方面提出了重大挑战.
研究的目的:
- 阐明由BPP合成酶从格兰二酸盐合成博尼尔二酸盐 (BPP) 的详细反应机制.
- 调查导致产品保真性和烯循环酶活性中的副产品形成的因素.
主要方法:
- 利用最先进的计算模拟方法.
- 进行化学动力学模拟以分析反应轨迹和能量景观.
主要成果:
- 确定波尼尔离子是自由能量表面的关键分叉点,将BPP和坎形成联系起来.
- 模拟表明,活性部位二酸盐部分引导对所需的BPP产品的反应.
结论:
- 酶诱导的分叉和二酸盐部分的影响解释了BPP和副产品坎的形成.
- 化学动力学精度固有的局限性解释了散乱的烯循环中缺乏绝对忠实性的原因.
相关概念视频
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Selection Rules: Photochemical Activation
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