双核非血铁酶AurF对电友反应的过氧激活
Kiyoung Park1,2, Ning Li3, Yeonju Kwak1
1Department of Chemistry, Stanford University , Stanford, California 94305-5080, United States.
Journal of the American Chemical Society
|May 2, 2017
概括
质子化激活双核非血铁酶中的过氧中间体,如AurF,用于关键的氧化反应. 这一发现揭示了酶催化的主要结构和电子要求.
科学领域:
- 生物化学
- 生物有机化学
- 酵素学
背景情况:
- 双核非血铁酶利用O2进行氧化和原子抽取.
- 过桥式双铁中间体是常见的,但并不总是有反应性.
- 了解这些中间体的激活是酶功能的关键.
研究的目的:
- 阐明激活过氧反应的几何和电子结构要求.
- 描述4-氨基酸N-氧化酶 (AurF) 中的活性过氧中间体.
主要方法:
- 减少 AurF 的磁圆二极化 (MCD) 光谱.
- 核共振振谱 (NRVS) 用于确定过氧中间体.
- 密度函数理论 (DFT) 的计算.
主要成果:
- 它们的电子和几何结构能够与氧气进行快速反应.
- 活性过氧中间体具有质子过氧桥.
- DFT计算证实质子激活过氧化物用于电友性/单电子转移反应.
结论:
- 质子化是AurF中过氧化物中间体激活的关键机制.
- 这种激活策略可能在其他双核非血铁酶中保持.
- 这项研究提供了金属酶激活氧气的催化机制的见解.
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