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化物 рибо开关识别部位的结构稳定性,酸度和化物选择性
Mohit Chawla1, Raffaele Credendino, Albert Poater
1KAUST Catalysis Research Center, Physical Sciences and Engineering Division, King Abdullah University of Science and Technology , Thuwal 23955-6900, Kingdom of Saudi Arabia.
Journal of the American Chemical Society
|December 10, 2014
概括
化物 рибо开关是一个化物 рибо开关.
科学领域:
- 生物化学 生物化学
- 计算化学计算化学
- 分子生物学分子生物学
背景情况:
- 丝带切换器是调节基因表达的RNA分子,以响应小分子.
- 化物 рибо开关是一种专门结合化物离子的 рибо开关类.
- 了解化物结合的结构和化学基础对于其生物功能至关重要.
研究的目的:
- 为了研究化物 рибо开关中Mg2+) /F(-) /酸盐/水集群的稳定性和结构性质.
- 为了确定对化物 рибо开关的化物选择性负责的因素.
- 阐明金属化物键在化物结合RNA结构的功能中的作用.
主要方法:
- 密度函数理论 (DFT) 方法,包括静态和动态模拟.
- 对集群稳定性,pKa预测和金属化物键强度的分析.
- 化物与化物结合的比较分析.
主要成果:
- 2+) /F-) /酸盐/水集群本质上是稳定的,不需要额外的RNA结构支持.
- 桥梁水分子的预测pKa大约是8.4.4.
- 化物 рибо开关的选择性归因于更强的Mg-F键,它保持了集群完整性.
- 用化物取代化物导致在动态条件下不稳定的集群.
- 在化物抑制的酸酶中观察到类似的发现,突出显示了金属化物键的强度.
结论:
- 2+) /F-) /酸盐/水集群的内在稳定性是化物 рибо开关功能的关键.
- 与Mg-Cl键相比,Mg-F键的强度更强,这决定了化物选择性.
- 化物形成强金属化物键的独特能力是其在生物系统中的核心作用.
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