合成,结构和电子特性 [8Fe-7S] 集群复合物模拟酶P-集群的集群复合物
Yasuhiro Ohki1, Motosuke Imada, Ayuro Murata
1Department of Chemistry, Graduate School of Science and Research Center for Materials Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan.
Journal of the American Chemical Society
|August 22, 2009
概括
这项研究提出了一种新的铁硫集群合成方法,模仿酶P(N) . 这些合成模型展示了本地P集群的氧化还原行为,这对于固定至关重要.
科学领域:
- 生物有机化学 生物有机化学
- 有机金属化学 有机金属化学
- 生物化学 生物化学
背景情况:
- 基酶酶对于生物固定的作用至关重要.
- 铁硫P (N) 集群是基酶的关键组成部分,参与电子转移.
- 了解P(N) 集群的结构-功能关系对于生物启发的催化是至关重要的.
研究的目的:
- 为模仿化酶P (N) 集群的 [8Fe-7S] 集群开发高产合成路径.
- 为了研究这些合成模型的配体交换和氧化还原特性.
- 阐明P(N) 集群的结构和电子特征及其氧化还原状态.
主要方法:
- 使用铁前体,硫醇,硫尿素和元素硫的铁硫集群的高产合成.
- 在低温 (-40°C) 的联结体交换反应中引入酸联结体.
- 使用X射线分析进行结构性表征.
- 通过循环电压计进行电化学研究.
- 光谱分析包括EPR和莫斯巴尔光谱学.
- 测量磁感应度的测量.
主要成果:
- 成功合成了[8Fe-7S]集群[{N(SiMe(3)) ((2)}{SC(NMe(2)) ((2)}Fe(4) S(3)](2)(mu(6) -S) {mu-N(SiMe(3)) 的高产合成和相关化合物.
- 一系列 [8Fe-7S] 集群的合成,具有不同的硫酸盐连接体,结构上类似于P(N) 集群.
- 在8Fe(II) (P(N)) 和6Fe(II) - 2Fe(III) (P(OX)) 状态之间的氧化还原行为的证明.
- 观察到EPR静音性质和单一基态与反铁磁合.
- 莫斯巴乌尔光谱证实了6Fe (II) - 2Fe (III) 的氧化状态,Fe (III) 定位在外围部位.
结论:
- 合成的 [8Fe-7S] 集群准确地模拟了酶 P(N) 集群的结构和氧化还原特性.
- 连接物修饰影响了集群的减少潜力.
- 周围的铁原子被确定为氧化到Fe (III) 的位置.
- 这些模型为酶活性机制提供了宝贵的见解.
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