Class-A penicillin binding proteins do not contribute to cell shape but repair cell-wall defects

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

The following data sets were generated

Article and author information

Author details

  1. Antoine Vigouroux

    Microbial Morphogenesis and Growth Laboratory, Institut Pasteur, Paris, France
    Competing interests
    The authors declare that no competing interests exist.
  2. Baptiste Cordier

    Microbial Morphogenesis and Growth Laboratory, Institut Pasteur, Paris, France
    Competing interests
    The authors declare that no competing interests exist.
  3. Andrey Aristov

    Microbial Morphogenesis and Growth Laboratory, Institut Pasteur, Paris, France
    Competing interests
    The authors declare that no competing interests exist.
  4. Laura Alvarez

    Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, Umeå, Sweden
    Competing interests
    The authors declare that no competing interests exist.
  5. Gizem Özbaykal

    Microbial Morphogenesis and Growth Laboratory, Institut Pasteur, Paris, France
    Competing interests
    The authors declare that no competing interests exist.
  6. Thibault Chaze

    Proteomics Platform, Institut Pasteur, Paris, France
    Competing interests
    The authors declare that no competing interests exist.
  7. Enno Rainer Oldewurtel

    Microbial Morphogenesis and Growth Laboratory, Institut Pasteur, Paris, France
    Competing interests
    The authors declare that no competing interests exist.
  8. Mariette Matondo

    Proteomics Platform, Institut Pasteur, Paris, France
    Competing interests
    The authors declare that no competing interests exist.
  9. Felipe Cava

    Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, Umeå, Sweden
    Competing interests
    The authors declare that no competing interests exist.
  10. David Bikard

    Synthetic Biology Laboratory, Institut Pasteur, Paris, France
    Competing interests
    The authors declare that no competing interests exist.
  11. Sven van Teeffelen

    Microbial Morphogenesis and Growth Laboratory, Institut Pasteur, Paris, France
    For correspondence
    sven.vanteeffelen@gmail.com
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0877-1294

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.

Reviewing Editor

  1. Jie Xiao, Johns Hopkins University, United States

Publication history

  1. Received: September 18, 2019
  2. Accepted: January 4, 2020
  3. Accepted Manuscript published: January 6, 2020 (version 1)
  4. Version of Record published: February 5, 2020 (version 2)

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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  1. Antoine Vigouroux
  2. Baptiste Cordier
  3. Andrey Aristov
  4. Laura Alvarez
  5. Gizem Özbaykal
  6. Thibault Chaze
  7. Enno Rainer Oldewurtel
  8. Mariette Matondo
  9. Felipe Cava
  10. David Bikard
  11. Sven van Teeffelen
(2020)
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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