在三铜集群中的多个质子合电子转移:在多铜氧化酶中建模减少再生过程
Weiyao Zhang1, Curtis E Moore1, Shiyu Zhang1
1Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States.
Journal of the American Chemical Society
|January 19, 2022
概括
合成的三铜复合体通过积累多个电子和质子来模仿大自然的氧化还原潜力平衡效应. 这项研究揭示了合成集群中可切换的质子合电子转移机制,实现了高效的多电子减少.
科学领域:
- 生物有机化学
- 协调化学
- 催化剂
背景情况:
- 酶性金属集群实现了氧化还原潜力的平衡,这对于维持生命的反应至关重要,这是一个尚未通过合成复制的壮举.
- 多铜氧化酶 (MCOs) 使用三核铜集群进行高效的电子和质子转移,但它们的机制仍然不完全理解.
- 合成模型对于解剖MCO中复杂的质子-合电子转移 (PCET) 过程至关重要.
研究的目的:
- 合成和描述一个完全封装的三铜复合体,能够模拟MCO中的三核铜集群的还原再生.
- 在模仿MCO氧化还原行为的合成系统中研究质子合电子转移 (PCET) 的机械路径.
- 通过在狭窄的电位范围内实现多电子的减少,证明合成金属集群中的氧化还原电位平衡效应.
主要方法:
- 一种新型三复合物的合成和完全封装.
- 使用光谱学和X射线单晶衍射对七个离散的氧化和质子化状态进行表征.
- 电子转移-质子转移 (ET-PT) 和质子转移-电子转移 (PT-ET) 路径的机制阐明.
主要成果:
- 合成三铜复合物成功模拟了MCOs中原产中间体的三电子,两质子减少.
- 根据氧化和质子化状态,观察到ET-PT和PT-ET之间可切换的机制.
- 七个不同的三铜复合体的特征,提供了详细的结构和电子洞察力.
- 三个电子,两个质子的减少发生在狭窄的170mV电位范围内,证明了氧化还原电位平衡.
结论:
- 合成三铜复合物有效地复制了在MCO中观察到的氧化还原潜力平衡效应.
- 观察到的可切换PCET机制突显了合成集群在模仿生物过程中的适应性.
- 这项工作为了解金属酶中电子和质子转移的基本原理提供了有价值的合成平台.
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