由单分子FRET揭示的P型ATPase运输的动力学
Mateusz Dyla1,2,3, Daniel S Terry4, Magnus Kjaergaard1,2,3,5
1Centre for Membrane Pumps in Cells and Disease - PUMPKIN, Danish National Research Foundation & Danish Research Institute of Translational Neuroscience - DANDRITE, Nordic-EMBL Partnership for Molecular Medicine, Aarhus University, DK-8000 Aarhus C, Denmark.
Nature
|November 17, 2017
概括
研究人员使用单分子FRET直接观察了运输的P型ATPases的结构变化. 流量受到酶形成的限制,揭示了关键的运输中间体.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 结构生物学 结构生物学
背景情况:
- P型ATPases是必不可少的膜蛋白,可以运输离子.
- 它们的功能依赖于与ATP水解相结合的结构变化.
- 了解这些动态对于细胞离子平衡至关重要.
研究的目的:
- 在其运输周期期间直接观察Ca2+-ATPase (LMCA1) 的构造变化.
- 为了识别以前在结构上没有可视化的功能中间体.
- 为了阐明流量中的速度限制步骤.
主要方法:
- 使用单分子光共振能量转移 (smFRET).
- 对Listeria monocytogenes Ca2+-ATPase (LMCA1) 的形态动态进行了监测.
- 功能转变与观察到的结构变化相关.
主要成果:
- 在运输周期中确定了关键的,不具特征的中间体.
- 由LMCA1调解的Ca2+流量被发现是由酶形成的速度限制.
- 运输机制涉及不同的可逆和不可逆转的步骤.
结论:
- 使用smFRET可以直接观察P型ATPase构造变化.
- 酶的形成是Ca2+运输速率的关键决定因素.
- 这项研究提供了关于阴阳运输的全性机制的新见解.
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