Sicoli, G, Konijnenberg, A, Guérin, J et al. (11 more authors) (2022) Large-Scale Conformational Changes of FhaC Provide Insights Into the Two-Partner Secretion Mechanism. Frontiers in Molecular Biosciences, 9. 950871. ISSN 2296-889X
Abstract
The Two-Partner secretion pathway mediates protein transport across the outer membrane of Gram-negative bacteria. TpsB transporters belong to the Omp85 superfamily, whose members catalyze protein insertion into, or translocation across membranes without external energy sources. They are composed of a transmembrane β barrel preceded by two periplasmic POTRA domains that bind the incoming protein substrate. Here we used an integrative approach combining in vivo assays, mass spectrometry, nuclear magnetic resonance and electron paramagnetic resonance techniques suitable to detect minor states in heterogeneous populations, to explore transient conformers of the TpsB transporter FhaC. This revealed substantial, spontaneous conformational changes on a slow time scale, with parts of the POTRA2 domain approaching the lipid bilayer and the protein’s surface loops. Specifically, our data indicate that an amphipathic POTRA2 β hairpin can insert into the β barrel. We propose that these motions enlarge the channel and initiate substrate secretion. Our data propose a solution to the conundrum how TpsB transporters mediate protein secretion without the need for cofactors, by utilizing intrinsic protein dynamics.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2022 Sicoli, Konijnenberg, Guérin, Hessmann, Del Nero, Hernandez-Alba, Lecher, Rouaut, Müggenburg, Vezin, Cianférani, Sobott, Schneider and Jacob-Dubuisson. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). |
Keywords: | outer membrane protein, protein dynamics, Omp85 superfamily, NMR, EPR, mass spectrometry, Gram-negative bacteria, two-partner secretion system |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Biological Sciences (Leeds) > School of Molecular and Cellular Biology (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 12 Dec 2022 13:52 |
Last Modified: | 12 Dec 2022 13:52 |
Status: | Published |
Publisher: | Frontiers Media |
Identification Number: | 10.3389/fmolb.2022.950871 |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:193935 |