六个Enterococcus hiraeV型ATPase的状态显示,在周转过程中旋转器的旋转不均
Raymond N Burton-Smith1,2, Chihong Song1,2,3, Hiroshi Ueno4
1Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, 38 Nishigonaka, Myodaiji, Okazaki, Aichi, 444-8585, Japan.
Communications biology
|July 28, 2023
概括
Enterococcus hirae真空类型的ATPase (EhV-ATPase),是Na+运输的独一无二,显示了六个结构状态. 不均的转子旋转和核酸结合口袋解释了其复杂的机制.
科学领域:
- 生物化学 生化学
- 结构生物学 结构生物学
- 分子生物物理学 分子生物物理学
背景情况:
- 真空型ATPases (V-ATPases) 是细胞过程中必不可少的质子.
- Enterococcus hirae V-ATPase (EhV-ATPase) 是独一无二的,它表现出Na+运输和一个离轴转子.
- 以前的研究表明V-ATPase旋转中的子状态,但缺乏结构证据.
研究的目的:
- 为EhV-ATPase旋转机制中的子状态提供第一个结构证据.
- 阐明EhV-ATPase独特的Na+运输和离轴旋转的结构基础.
- 在ATP循环过程中描述EhV-ATPase在ATP循环过程中的不同催化状态.
主要方法:
- 使用冷电子显微镜 (cryo-EM) 来捕捉多个结构状态.
- 用ATP激活EhV-ATPase复合体,以观察其动态行为.
- 对核酸结合口袋和转子 - 定子相互作用的分析提供了机械的见解.
主要成果:
- 确定了EhV-ATPase复合体的六个不同的结构状态.
- 这项研究揭示了在酶循环过程中转子方向的不均性,特别是在中间状态.
- 核酸结合口袋密度的变化表明在观察到的构造中存在不同的催化条件.
结论:
- 结构数据支持在EhV-ATPase中存在多个功能子状态.
- 离轴转子组件及其与定位器的相互作用有助于观察到的不均旋转.
- 这些发现为EhV-ATPase的独特旋转机制和Na+运输提供了更深入的理解.
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