在单核非海姆铁复合体中,是什么驱动激素化与化? 一个结合实验和计算的研究
Emilie F Gérard1,2, Vishal Yadav3, David P Goldberg3
1Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom.
Journal of the American Chemical Society
|May 10, 2022
概括
非海姆铁基酶选择性地将基 (X•) 转移到二次碳基,而不是三级基,其中反应是 endergonic. 这种选择性取决于热力学稳定性和二次协调球效应.
科学领域:
- 生物化学
- 酵素学
- 有机金属化学
背景情况:
- 非血铁酶激活异形C-H键,将它们转化为C-X (X = Cl, Br).
- 这些酶被建议在催化过程中产生FeIII
- 一个关键的辩论围绕着控制这些酶显著选择性的因素.
研究的目的:
- 研究FeIII的反应性.
- 使用计算方法阐明酶反应的选择性起源.
主要方法:
- 用二次碳基对FeIII(BNPAPh2) 复合物的实验研究.
- 使用密度函数理论 (DFT) 的综合计算研究.
主要成果:
- 在二次碳基中观察到素 (X•) 转移,而在三级碳基中观察到基 (OH•) 转移.
- DFT计算重现了实验结果,显示基转移是不利于三级激素,因为无效的,非生产平衡.
- 对于二次基来来说,转移是有利的,因为产物复合物在热力学上更稳定.
结论:
- 非铁化酶的选择性取决于化产品复合物的热力学稳定性,这种稳定性对二级碳中心比三级碳中心更有利.
- 二次协调球效应,如固态和键相互作用,显著影响转移的反应屏障.
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