Fessl, T orcid.org/0000-0001-6969-4870, Watkins, D, Oatley, P et al. (7 more authors) (2018) Dynamic action of the Sec machinery during initiation, protein translocation and termination. eLife, 7. e35112. ISSN 2050-084X
Abstract
Protein translocation across cell membranes is a ubiquitous process required for protein secretion and membrane protein insertion. In bacteria, this is mostly mediated by the conserved SecYEG complex, driven through rounds of ATP hydrolysis by the cytoplasmic SecA, and the trans-membrane proton motive force. We have used single molecule techniques to explore SecY pore dynamics on multiple timescales in order to dissect the complex reaction pathway. The results show that SecA, both the signal sequence and mature components of the pre-protein, and ATP hydrolysis each have important and specific roles in channel unlocking, opening and priming for transport. After channel opening, translocation proceeds in two phases: a slow phase independent of substrate length, and a length-dependent transport phase with an intrinsic translocation rate of ~40 amino acids per second for the proOmpA substrate. Broad translocation rate distributions reflect the stochastic nature of polypeptide transport.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | Copyright Fessl et al. This article is distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use and redistribution provided that the original author and source are credited. |
Keywords: | single molecule fluorescence, protein export, kinetics |
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) > Structural Molecular Biology (Leeds) |
Funding Information: | Funder Grant number BBSRC (Biotechnology & Biological Sciences Research Council) BB/N017307/1 |
Depositing User: | Symplectic Publications |
Date Deposited: | 11 Jun 2018 11:29 |
Last Modified: | 27 Aug 2022 16:42 |
Status: | Published |
Publisher: | eLife Sciences Publications |
Identification Number: | 10.7554/eLife.35112 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:131829 |