伊米达酸盐合成酶的几百万秒钟激活的时间演变
Carla Calvó-Tusell1, Miguel A Maria-Solano1,2, Sílvia Osuna1,3
1Institut de Química Computacional i Catàlisi (IQCC) and Departament de Química, Universitat de Girona, c/Maria Aurèlia Capmany 69, 17003 Girona, Catalonia, Spain.
Journal of the American Chemical Society
|April 12, 2022
概括
这项研究揭示了 imidazole glycerol phosphate synthase (IGPS) 的毫秒级分子激活机制. 计算方法显示了效应器和基质结合如何触发高效的谷氨酸水解的结构变化.
科学领域:
- 生物化学和分子生物学
- 计算生物物理学
背景情况:
- 酶性基调控对于细胞过程至关重要.
- 鉴定像伊米达酸酶 (IGPS) 这样的酶的短暂功能状态和毫秒动态仍然具有挑战性.
- 了解IGPS全激活是解读其催化机制的关键.
研究的目的:
- 阐明IGPS异质激活的分子机制和时间演变.
- 描述从无基质形式过渡到活性三元复合体.
- 为了揭示IGPS长距离毫秒调节的隐藏分子细节
主要方法:
- 进行广泛的分子动力学模拟.
- 提升采样技术.
- 动态网络分析
主要成果:
- 在没有事先了解活性状态的情况下,模拟显示了谷氨酸的自发捕获和活性三元复合物的形成.
- 该研究确定了关键的结构变化: HisF:HisH接口和HisH中的氧离子孔形成.
- 效应器和基质结合显著降低了氧化离子孔形成的构造障碍,解释了4500倍的活性增加.
结论:
- IGPS的全位激活是由关联的动态网络驱动的,这些网络连接了效应器和基质的结合点.
- 计算策略成功地描述了酶性调节中的毫秒时间尺度事件.
- 这种方法可以指导IGPS工程并合理化突变对全调节的影响.
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