Sanganna Gari, R.R., Montalvo‐Acosta, J.J., Heath, G.R. orcid.org/0000-0001-6431-2191 et al. (5 more authors) (2021) Correlation of membrane protein conformational and functional dynamics. Nature Communications, 12. 4363. ISSN 2041-1723
Abstract
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.
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Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © The Author(s) 2021. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. |
Keywords: | Escherichia coli; Lipid Bilayers; Bacterial Outer Membrane Proteins; Porins; Escherichia coli Proteins; Ion Channels; Recombinant Proteins; Microscopy, Atomic Force; Spectrum Analysis; Electrophysiology; Ion Channel Gating; Protein Conformation; Structure-Activity Relationship; Hydrogen-Ion Concentration; Molecular Dynamics Simulation; Protein Conformation, beta-Strand |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Physics and Astronomy (Leeds) > Molecular & Nanoscale Physics |
Depositing User: | Symplectic Publications |
Date Deposited: | 27 Feb 2024 11:58 |
Last Modified: | 27 Feb 2024 11:58 |
Status: | Published |
Publisher: | Nature Research |
Identification Number: | 10.1038/s41467-021-24660-1 |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:209619 |
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