Class-A penicillin binding proteins do not contribute to cell shape but repair cell-wall defects
- Institut Pasteur, France
- Umeå University, Sweden
Abstract
Cell shape and cell-envelope integrity of bacteria are determined by the peptidoglycan cell wall. In rod-shaped Escherichia coli, two conserved sets of machinery are essential for cell-wall insertion in the cylindrical part of the cell: the Rod complex and the class-A penicillin-binding proteins (aPBPs). While the Rod complex governs rod-like cell shape, aPBP function is less well understood. aPBPs were previously hypothesized to either work in concert with the Rod complex or to independently repair cell-wall defects. First, we demonstrate through modulation of enzyme levels that aPBPs do not contribute to rod-like cell shape but are required for mechanical stability, supporting their independent activity. By combining measurements of cell-wall stiffness, cell-wall insertion, and PBP1b motion at the single-molecule level we then present evidence that PBP1b, the major aPBP, contributes to cell-wall integrity by repairing cell wall defects.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files or deposited on Dryad. Source data files have been provided for Figures 1-4.Dryad datasets:Tracking data Tracking.zip: https://doi.org/10.5061/dryad.m37pvmcxq.SDS-Page raw images: https://doi.org/10.5061/dryad.9s4mw6mb9
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Class-A penicillin binding proteins do not contribute to cell shape but repair cell-wall defects - Tracking datasetDryad Digital Repository, doi:10.5061/dryad.m37pvmcxq.
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Class-A penicillin binding proteins do not contribute to cell shape but repair cell-wall defects - SDS Page raw imagesDryad Digital Repository, doi:10.5061/dryad.9s4mw6mb9.
Article and author information
Author details
Sven van Teeffelen
Funding
H2020 European Research Council (679980)
- Sven van Teeffelen
Agence Nationale de la Recherche (ANR-10-LABX-62-IBEID)
- Antoine Vigouroux
- David Bikard
- Sven van Teeffelen
Volkswagen Foundation
- Sven van Teeffelen
Mairie de Paris (Emergence(s))
- Sven van Teeffelen
H2020 European Research Council (677823)
- David Bikard
Knut och Alice Wallenbergs Stiftelse
- Felipe Cava
Swedish Research Council
- Felipe Cava
Kempe Foundation
- Felipe Cava
Laboratory for Molecular Infection Medicine Sweden
- Felipe Cava
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Vigouroux et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Class-A penicillin binding proteins do not contribute to cell shape but repair cell-wall defects
eLife 9:e51998.
https://doi.org/10.7554/eLife.51998
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