基于Calix[6]arene的铜"道复合物":模仿基质进入金属酶活性位点的通道
Yannick Rondelez1, Marie-Noëlle Rager, Arthur Duprat
1Laboratoire de Chimie et Biochimie Pharmacologiques et Toxicologiques, CNRS UMR 8601, Université René Descartes, 45 rue des Saints-Pères, 75270 Paris Cedex 06, France.
Journal of the American Chemical Society
|February 14, 2002
概括
单铜酶的Calixarene模型显示了腔体大小如何影响有机尼铁结合. 系统B,具有更大的腔,表现出更快的酸交换,模仿酶活性部位通道.
科学领域:
- 超分子化学 超分子化学
- 生物有机化学 生物有机化学
- 酵素仿真是一种很好的方法.
背景情况:
- 单铜酶利用富含伊米达的铜离子协调部位.
- 卡利沙支架提供可调节的疏水性腔体,用于分子识别.
- 开发合成模型对于理解酶机制至关重要.
研究的目的:
- 为了比较两个基于calixarene的单铜酶模型系统.
- 调查腔体大小和结构对铜 (I) 复合和有机尼铁结合的影响.
- 为了阐明在铜 (I) 中心的酸交换机制.
主要方法:
- 合成两种三 (?? 里丁) 基铜 (I) 复合物 (a和b系统).
- 四面体铜 (I) 复合体与有机尼铁连接体的特征.
- 使用 (1) H NMR光谱学研究乙尼铁交换动力学和热力学.
主要成果:
- 这两种系统都形成了四面体铜 (I) 复合体,在calixarene腔内与有机尼特里尔.
- 与系统a相比,具有较大的空腔的系统b显示了反向的识别模式和相亲常数的三次大小差异.
- 乙酸交换遵循一个分离的路径,系统b由于其更广泛的开放,显示出100倍更快的交换率.
结论:
- 酸腔的大小和结构显著影响铜复合体中的基质识别和结合亲和力.
- 系统a中的"门"效应会影响客人的捕获和交换动力学.
- 这些超分子系统是导致金属酶活性位点的疏水通道的宝贵模型.
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