在 pyranopterin dithiolene 中的结构和可逆的 pyran 形成是辅因子的 pyranopterin dithiolene 模型
Benjamin R Williams1, Yichun Fu, Glenn P A Yap
1Department of Chemistry, Bryn Mawr College, Bryn Mawr, Pennsylvania 19010-2899, United States.
Journal of the American Chemical Society
|November 20, 2012
概括
研究人员合成了 pyranopterin dithiolene 复合物,揭示了一个新的 pyran 环形成. 在溶液中的这种动态循环反应表明,和酶在酶催化中起着作用.
科学领域:
- 生物有机化学 生物有机化学
- 协调化学 协调化学
- 结构生物学 结构生物学
背景情况:
- 和酶在生物氧化还原反应中起着至关重要的作用.
- 素连接体是这些金属酶活性位点的关键组成部分.
- 了解连接体的协调环境和动态对于阐明酶机制至关重要.
研究的目的:
- 在生物学相关的氧化状态下合成和表征 pyranopterin dithiolene 复合物 (Mo(4+) 和 Mo(5+)).
- 调查这些复合物的结构特征和溶液行为,特别是Pyran环的形成和动态.
- 提供对和酶的潜在催化机制的实验性见解,其中涉及pyranopterin dithiolene连接体.
主要方法:
- 聚合 pyranopterin 滴醇烯复合物的合成.
- 用于结构确定的X射线晶体学.
- 核磁共振 (NMR) 谱学用于研究溶液动力学.
主要成果:
- 两种 pyranopterin dithiolene 复合物成功合成,并通过 X 射线确定了它们的结构.
- 一个自发的循环反应涉及dithiolene侧链基团和pterin CN键形成了一个pyran环.
- 核磁共振 (NMR) 数据表明,这种pyran环循环化在Mo(4+) 复合体的溶液中是可逆的.
结论:
- 皮拉诺二醇烯连接体可以经历动态循环,形成一个pyran环.
- 在溶液中观察到的这种动态行为为连接体在酶催化中的潜在作用提供了实验证据.
- 蛋白质环境可能会调节和酶中的这些动态过程.
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