A pH-independent quiet OmpG pore with enhanced electrostatic repulsion among the extracellular loops.
A pH-independent quiet OmpG pore with enhanced electrostatic repulsion among the extracellular loops.
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DOI：
10.1016/j.bbamem.2020.183485
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发表时间：
2021-01-01
期刊：
影响因子：
--
通讯作者：
Chen M
中科院分区：
文献类型：
--
作者：
Pham B;Chisholm CM;Foster J;Friis E;Fahie MA;Chen M
膜蛋白孔已成为单分子检测的强大纳米孔传感器。OmpG是一种单体纳米孔，由14条β链组成，由7个柔性的细胞外环连接。平面脂质双分子层研究显示，OmpG纳米孔具有ph依赖性门控。目前的证据有力地表明，环路6的动态运动是负责门控机制。在这项工作中，我们已经表明，增强细胞外环之间的静电斥力抑制ph依赖性门控。与野生型OmpG相比，我们的突变体在环6和环1中含有额外的负电荷，表现出最小的自发门控，对pH变化的敏感性降低。这些结果为支持门控环周围复杂静电网络控制OmpG门控机理提供了新的证据。与pH无关的安静的OmpG孔可能被用作在广泛的pH条件下工作的传感平台。
Membrane protein pores have emerged as powerful nanopore sensors for single-molecule detection. OmpG, a monomeric nanopore, is comprised of fourteen β-strands connected by seven flexible extracellular loops. The OmpG nanopore exhibits pH-dependent gating as revealed by planar lipid bilayer studies. Current evidence strongly suggests that the dynamic movement of loop 6 is responsible for the gating mechanism. In this work, we have shown that enhancing the electrostatic repulsion forces between extracellular loops suppressed the pH-dependent gating. Our mutant containing additional negative charges in loop 6 and loop 1 exhibited minimal spontaneous gating and reduced sensitivity to pH changes compared to the wild type OmpG. These results provide new evidence to support the mechanism of OmpG gating controlled by the complex electrostatic network around the gating loop 6. The pH-independent quiet OmpG pores could potentially be used as a sensing platform that operates at a broad range of pH conditions.
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影响因子：
16.6
作者：
Retel JS;Nieuwkoop AJ;Hiller M;Higman VA;Barbet-Massin E;Stanek J;Andreas LB;Franks WT;van Rossum BJ;Vinothkumar KR;Handel L;de Palma GG;Bardiaux B;Pintacuda G;Emsley L;Kühlbrandt W;Oschkinat H
通讯作者：
Oschkinat H
DOI：
10.1016/j.bbapap.2008.11.005
发表时间：
2009-05
期刊：
Biochimica et biophysica acta
影响因子：
--
作者：
Delcour AH
通讯作者：
Delcour AH
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
影响因子：
3.4
作者：
Alcaraz, A;Nestorovich, EM;Bezrukov, SM
通讯作者：
Bezrukov, SM
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.