水会找到它自己的路:通过窄道运输在Hydrolases
Carlos Sequeiros-Borja1,2, Bartlomiej Surpeta1,2, Aravind Selvaram Thirunavukarasu1,2
1International Institute of Molecular and Cell Biology, Warsaw 02-109, Poland.
Journal of chemical information and modeling
|April 26, 2024
概括
蛋白质通过狭窄的道运输水,挑战了以前的假设. 这项研究揭示了这些被忽视的途径对于生化过程和酶功能至关重要.
科学领域:
- 生物化学 生化学
- 结构生物学 结构生物学
- 计算生物学 计算生物学
背景情况:
- 水对生命和蛋白质功能至关重要,在酶活性和稳定性中发挥关键作用.
- 蛋白质介导的水运输对细胞过程至关重要,但仍未得到充分研究,特别是在内部蛋白质网络中.
- 通过蛋白质道进行分子运输的研究在实验上很困难,因此计算模拟是必不可少的.
研究的目的:
- 通过三种α/β-水解酶的内部道研究水分子运输:环甲基脱酶,环氧化水解酶和脂酶.
- 分析狭窄道和亚斯特罗姆瓶在蛋白质介导水运输中的作用.
- 了解分子机制,包括结,通过狭窄的蛋白质通路促进水的运输.
主要方法:
- 使用适应性分子动力学模拟,每个酶系统的持续时间为5μs.
- 分析了不同α/β-水解酶的水分子轨迹和道使用情况.
- 在狭窄的道内,水分子和蛋白质残留物之间的定量化键形成.
主要成果:
- 观察到一些道在脱酶中主导水运输,而其他酶则显示活性道的分布更广泛.
- 证明水分子可以成功地穿过具有亚斯特罗姆瓶的极窄道,这与基于水分子大小的预期相反.
- 在狭窄的道内发现了键的显著增加,弥补了水运输期间的硬质约束.
- 确定这些狭窄的,被忽视的道对总水运输的贡献约为20%.
结论:
- 该研究强调了狭窄的蛋白质道在促进水运输方面的重要,但经常被忽视的作用.
- 这些发现需要在定义水运输功能蛋白道时重新评估几何约束.
- 获得的见解可以解释酶突变的功能差异,例如与缺血性中风相关的人类可溶性环氧化酶突变.
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