Correlation of membrane protein conformational and functional dynamics.
Correlation of membrane protein conformational and functional dynamics.
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DOI：
10.1038/s41467-021-24660-1
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发表时间：
2021-07-16
影响因子：
16.6
通讯作者：
Scheuring S
中科院分区：
文献类型：
--
作者：
Sanganna Gari RR;Montalvo-Acosta JJ;Heath GR;Jiang Y;Gao X;Nimigean CM;Chipot C;Scheuring S
离子通道的构象变化导致离子导电孔的门控。几十年来，单通道电生理技术对离子通量进行了高时间分辨率的测量。然而，功能和构象动力学之间的相关性仍然很困难，缺乏监测亚毫秒构象变化的实验技术。在这里，我们使用外膜蛋白G （OmpG）作为模型系统，其中环路6以ph依赖的方式打开和关闭像盖子一样的β桶孔。功能上，单通道电生理学表明，虽然在酸性pH下有利于封闭状态，而在生理pH下有利于开放状态，但这两种状态在所有条件下都是共存并快速交换的。利用HS-AFM高度光谱（HS-AFM- hs），我们监测亚毫秒环路6构象动力学，并将其与单通道记录的功能动力学进行比较，而MD模拟提供了依赖ph的环路6波动的原子细节和能量景观。HS-AFM-HS为在时域和环路波动的时间尺度上分析构象动力学提供了新的机会。使用高速原子力显微镜、高度光谱和单通道电生理记录来关联模型膜蛋白外膜蛋白G （OmpG）的构象和功能动力学。这些技术表明，在分子动力学模拟支持的所有条件下，这两种状态共存并快速交换。
Conformational changes in ion channels lead to gating of an ion-conductive pore. Ion flux has been measured with high temporal resolution by single-channel electrophysiology for decades. However, correlation between functional and conformational dynamics remained difficult, lacking experimental techniques to monitor sub-millisecond conformational changes. Here, we use the outer membrane protein G (OmpG) as a model system where loop-6 opens and closes the β-barrel pore like a lid in a pH-dependent manner. Functionally, single-channel electrophysiology shows that while closed states are favored at acidic pH and open states are favored at physiological pH, both states coexist and rapidly interchange in all conditions. Using HS-AFM height spectroscopy (HS-AFM-HS), we monitor sub-millisecond loop-6 conformational dynamics, and compare them to the functional dynamics from single-channel recordings, while MD simulations provide atomistic details and energy landscapes of the pH-dependent loop-6 fluctuations. HS-AFM-HS offers new opportunities to analyze conformational dynamics at timescales of domain and loop fluctuations. High-speed atomic force microscopy height spectroscopy and single channel electrophysiology recordings are used to correlate conformational and functional dynamics of the model membrane protein, outer membrane protein G (OmpG). These techniques show that both states coexist and rapidly interchange in all conditions supported by molecular dynamics simulations.
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影响因子：
3.3
作者：
Klauda, Jeffery B.;Venable, Richard M.;Freites, J. Alfredo;O'Connor, Joseph W.;Tobias, Douglas J.;Mondragon-Ramirez, Carlos;Vorobyov, Igor;MacKerell, Alexander D., Jr.;Pastor, Richard W.
通讯作者：
Pastor, Richard W.
DOI：
10.1073/pnas.0711561105
发表时间：
2008-04-29
影响因子：
11.1
作者：
Chen, Min;Khalid, Syma;Bayley, Hagan
通讯作者：
Bayley, Hagan
DOI：
10.1073/pnas.211400898
发表时间：
2001-10-23
影响因子：
11.1
作者：
Ando, T;Kodera, N;Toda, A
通讯作者：
Toda, A
DOI：
10.1073/pnas.0705466104
发表时间：
2007-10-09
影响因子：
11.1
作者：
Liang, Binyong;Tamm, Lukas K.
通讯作者：
Tamm, Lukas K.
影响因子：
2.9
作者：
Bas, Delphine C.;Rogers, David M.;Jensen, Jan H.
通讯作者：
Jensen, Jan H.