ATP 结合控制了细菌 MutS2 的分子功能,通过调解二维结构的关闭来控制其分子功能
Kenji Fukui1, Takeshi Murakawa1, Nobumasa Hino2
1Department of Biochemistry, Faculty of Medicine, Osaka Medical and Pharmaceutical University, 2-7 Daigaku-machi, Takatsuki, Osaka 569-8686, Japan.
Structure (London, England : 1993)
|March 29, 2025
概括
MutS2蛋白经历了依赖ATP的结构变化,关闭了它的形状. 这种关闭增强了与DNA重组中间体的结合,并有助于解决碰撞的核糖体.
科学领域:
- 分子生物学分子生物学
- 生物化学 生物化学
- 结构生物学 结构生物学
背景情况:
- MutS2蛋白识别了分支的DNA结构,并解决了碰撞的核糖体.
- 这些功能取决于ATP驱动的结构变化.
- 已知的结构显示MutS2在无核酸和ADP结合状态的开放形状.
研究的目的:
- 阐明MutS2.2的依赖ATP的结构变化.
- 确定MutS2在同源重组和核糖体循环中的作用的结构基础.
主要方法:
- MutS2的X射线晶体学与ATP类似物.
- 一种光交叉连接氨基酸的特定场所内置.
- 基于解决方案的交叉连接实验.
- DNA 结合测试.DNA 结合测试.
主要成果:
- MutS2与ATP类似物结合的晶体结构显示出一个封闭的合形状.
- 在溶液中使用光学交叉连接证实了依赖ATP的紧关闭.
- ATP结合加强了MutS2与无终端DNA的相互作用,但没有包含终端DNA的相互作用.
结论:
- 取决于ATP的紧关闭稳定了MutS2与重组中间体的结合,可能调节同源重组.
- 封闭的紧结构为对碰撞的核糖体的MutS2-介导解离提供了机械的洞察力.
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