一个单铁复合物的转化为 [2Fe-2S] 集群,由一个囊类同类物转化
Jessica Fitzpatrick1, Harris Kalyvas, Milos R Filipovic
1Department of Chemistry, Brown University , Providence, Rhode Island 02912, United States.
Journal of the American Chemical Society
|May 9, 2014
概括
研究人员展示了一种新的方法来修复受氧化 (NO) 损坏的铁硫[Fe-S]集群. 这一过程将单铁复合体 (MNIC) 转化为功能[Fe-S]集群,使用半氨酸类似物.
科学领域:
- 生物有机化学 生物有机化学
- 生物化学 生物化学
- 金属蛋白化学 金属蛋白化学
背景情况:
- 氧化 (NO) 在调节性蛋白质中可逆地修改铁硫[Fe-S]集群,作为遗传开关.
- 虽然NO诱导的[Fe-S]集群修饰得到了很好的研究,但反向过程 - - 修复这些集群 - - 仍然不太了解.
研究的目的:
- 为了研究氧化损坏的[Fe-S]集群的修复机制.
- 使用半氨酸模拟物,证明一个单氨酸铁复合体 (MNIC) 的转化回 [2Fe-2S] 集群.
主要方法:
- 将一个特定的MNIC, (PPN) [Fe(S(t) Bu) 3(NO) ] (1),转换为一个 [2Fe-2S] 集群, (PPN) 2[Fe2S2(SCH2CH2C(O) OMe) [4] (2),通过添加3-甲 (MMP).
- 使用光谱,化学,晶体学和分析方法对得到的集群进行表征.
- 使用质谱和 (34) S标签来追踪桥梁硫化物的来源并确定NO的捕获机制.
主要成果:
- 在室温下单独添加MMP成功将MNIC (1) 转换为 [2Fe-2S] 集群 (2).
- 谱学,化学,晶体学和分析数据证实了合成的 [2Fe-2S] 集群的身份.
- 质谱和 (34) S标签表明,MMP为修复的集群提供了桥梁硫化物.
- 释放的NO被有效地困在一个dinitrosyl铁复合体副产品中, (PPN) [Fe ((SCH2CH2C ((O) OMe) 2 ((NO) 2) ] (4).
结论:
- 单铁复合物 (MNIC) 可能是修复NO损坏的 [2Fe-2S] 集群中的中间体.
- 氨酸及其类似物是可活性的分子,可以破坏MNIC的稳定,并促进 [2Fe-S] 集群的形成.
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