完整的Thermus thermophilus H+驱动的ATP合成酶的亚纳米分辨率结构
Wilson C Y Lau1, John L Rubinstein
1Molecular Structure and Function Program, The Hospital for Sick Children Research Institute, 555 University Avenue, Toronto, Ontario M5G 1X8, Canada.
Nature
|December 20, 2011
概括
研究人员揭示了由质子驱动的ATP合成酶的结构,详细说明了离子流如何推动细胞能量生产. 这一突破澄清了在旋转ATPases中将质子动力转化为旋转的机制.
科学领域:
- 生物化学 生物化学
- 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:
- 离子转位旋转ATPases是关键的酶,它们要么使用离子梯度合成ATP,要么使用ATP水解离子.
- 这些酶拥有两个旋转电机,一个用于离子转位,另一个用于ATP合成/水解.
- 这些ATPase的完整膜区域的结构模型以前是不可用的.
研究的目的:
- 确定来自Thermus thermophilus的H(+) 驱动ATP合成酶的膜结合区域的高分辨率结构.
- 阐明一个跨膜质子动力转化为机械旋转的机制.
主要方法:
- 使用单粒子电子冷显微镜 (cryo-EM) 来获得9.7 Å分辨率的地图.
- 这项研究分析了600千多复合体,其子单元组成为A(3) B(3) CDE(2) FG(2) IL(12).
主要成果:
- 膜绑定电机包括一个12L子单元的环和一个有8个跨膜螺旋的I子单元.
- 在膜中心的L(12) 环和子单元I之间观察到一个小的接触区域.
- 小单元I的跨膜螺旋体形成捆绑,可能充当质子半通道,促进离子流动.
结论:
- 确定的结构为ATP合成酶的旋转机制提供了前所未有的洞察力.
- 这些发现表明了质子转移如何驱动中心旋转器的旋转的模型.
- 这项工作为了解这些重要细胞机器中的能量转化奠定了基础.
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