On the role of nucleotides and lipids in the polymerization of the actin homolog MreB from a Gram-positive bacterium

  1. Wei Mao
  2. Lars D Renner  Is a corresponding author
  3. Charlène Cornilleau
  4. Ines Li de la Sierra-Gallay
  5. Sana Afensiss
  6. Sarah Benlamara
  7. Yoan Ah-Seng
  8. Herman Van Tilbeurgh
  9. Sylvie Nessler  Is a corresponding author
  10. Aurélie Bertin  Is a corresponding author
  11. Arnaud Chastanet  Is a corresponding author
  12. Rut Carballido-Lopez  Is a corresponding author
  1. Micalis Institute, France
  2. Leibniz Institute of Polymer Research, Germany
  3. CNRS Université Paris-Saclay, France
  4. Institut Curie, France

Abstract

In vivo, bacterial actin MreB assembles into dynamic membrane-associated filamentous structures that exhibit circumferential motion around the cell. Current knowledge of MreB biochemical and polymerization properties in vitro remains limited and is mostly based on MreB proteins from Gram-negative species. In this study, we report the first observation of organized protofilaments by electron microscopy and the first 3D-structure of MreB from a Gram-positive bacterium. We show that Geobacillus stearothermophilus MreB forms straight pairs of protofilaments on lipid surfaces in the presence of ATP or GTP, but not in the presence of ADP, GDP or non-hydrolysable ATP analogs. We demonstrate that membrane anchoring is mediated by two spatially close short hydrophobic sequences while electrostatic interactions also contribute to lipid binding, and show that the population of membrane-bound protofilament doublets is in steady-state. In solution, protofilament doublets were not detected in any condition tested. Instead, MreB formed large sheets regardless of the bound nucleotide, albeit at a higher critical concentration. Altogether, our results indicate that both lipids and ATP are facilitators of MreB polymerization, and are consistent with a dual effect of ATP hydrolysis, in promoting both membrane binding and filaments assembly/disassembly.

Data availability

Protein structures data have been deposited in PDB under the accession codes 7ZPT and 8AZG.

The following data sets were generated

Article and author information

Author details

  1. Wei Mao

    Micalis Institute, Jouy-en-Josas, France
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0443-651X
  2. Lars D Renner

    Leibniz Institute of Polymer Research, Dresden, Germany
    For correspondence
    renner@ipfdd.de
    Competing interests
    The authors declare that no competing interests exist.
  3. Charlène Cornilleau

    Micalis Institute, Jouy-en-Josas, France
    Competing interests
    The authors declare that no competing interests exist.
  4. Ines Li de la Sierra-Gallay

    Institute for Integrative Biology of the Cell, CNRS Université Paris-Saclay, Gif-sur-Yvette, France
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2770-7439
  5. Sana Afensiss

    Micalis Institute, Jouy-en-Josas, France
    Competing interests
    The authors declare that no competing interests exist.
  6. Sarah Benlamara

    Micalis Institute, Jouy-en-Josas, France
    Competing interests
    The authors declare that no competing interests exist.
  7. Yoan Ah-Seng

    Micalis Institute, Jouy-en-Josas, France
    Competing interests
    The authors declare that no competing interests exist.
  8. Herman Van Tilbeurgh

    Institute for Integrative Biology of the Cell, CNRS Université Paris-Saclay, Gif-sur-Yvette, France
    Competing interests
    The authors declare that no competing interests exist.
  9. Sylvie Nessler

    Institute for Integrative Biology of the Cell, CNRS Université Paris-Saclay, Gif-sur-Yvette, France
    For correspondence
    Sylvie.NESSLER@i2bc.paris-saclay.fr
    Competing interests
    The authors declare that no competing interests exist.
  10. Aurélie Bertin

    Laboratoire Physico Chimie Curie, Institut Curie, Paris, France
    For correspondence
    aurelie.bertin@curie.fr
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3400-6887
  11. Arnaud Chastanet

    Micalis Institute, Jouy-en-Josas, France
    For correspondence
    arnaud.chastanet@inrae.fr
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0320-4861
  12. Rut Carballido-Lopez

    Micalis Institute, Jouy-en-Josas, France
    For correspondence
    rut.carballido-lopez@inrae.fr
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9383-8811

Funding

European Research Council (ERC-SG,311231)

  • Rut Carballido-Lopez

European Research Council (ERC-CG,772178)

  • Rut Carballido-Lopez

Agence Nationale de la Recherche (ANR-11-LABX0038)

  • Aurélie Bertin

Agence Nationale de la Recherche (ANR-10-IDEX-0001-02)

  • Aurélie Bertin

VolkswagenStiftung

  • Lars D Renner

Agence Nationale de la Recherche (ANR-10-INSB-05-05)

  • Sylvie Nessler

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Petra Anne Levin, Washington University in St. Louis, United States

Version history

  1. Preprint posted: October 20, 2022 (view preprint)
  2. Received: October 26, 2022
  3. Accepted: October 8, 2023
  4. Accepted Manuscript published: October 11, 2023 (version 1)

Copyright

© 2023, Mao 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. Wei Mao
  2. Lars D Renner
  3. Charlène Cornilleau
  4. Ines Li de la Sierra-Gallay
  5. Sana Afensiss
  6. Sarah Benlamara
  7. Yoan Ah-Seng
  8. Herman Van Tilbeurgh
  9. Sylvie Nessler
  10. Aurélie Bertin
  11. Arnaud Chastanet
  12. Rut Carballido-Lopez
(2023)
On the role of nucleotides and lipids in the polymerization of the actin homolog MreB from a Gram-positive bacterium
eLife 12:e84505.
https://doi.org/10.7554/eLife.84505

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