Lytic transglycosylases mitigate periplasmic crowding by degrading soluble cell wall turnover products

  1. Anna Isabell Weaver
  2. Laura Alvarez
  3. Kelly M Rosch
  4. Asraa Ahmed
  5. Garrett Sean Wang
  6. Michael S vanNieuwenhze
  7. Felipe Cava  Is a corresponding author
  8. Tobias Dörr  Is a corresponding author
  1. Cornell University, United States
  2. Umeå University, Sweden
  3. Indiana University, United States

Abstract

The peptidoglycan cell wall is a predominant structure of bacteria, determining cell shape and supporting survival in diverse conditions. Peptidoglycan is dynamic and requires regulated synthesis of new material, remodeling, and turnover - or autolysis - of old material. Despite exploitation of peptidoglycan synthesis as an antibiotic target, we lack a fundamental understanding of how peptidoglycan synthesis and autolysis intersect to maintain the cell wall. Here, we uncover a critical physiological role for a widely misunderstood class of autolytic enzymes, lytic transglycosylases (LTGs). We demonstrate that LTG activity is essential to survival by contributing to periplasmic processes upstream and independent of peptidoglycan recycling. Defects accumulate in Vibrio cholerae LTG mutants due to generally inadequate LTG activity, rather than absence of specific enzymes, and essential LTG activities are likely independent of protein-protein interactions, as heterologous expression of a non-native LTG rescues growth of a conditionally LTG-null mutant. Lastly, we demonstrate that soluble, uncrosslinked, endopeptidase-dependent peptidoglycan chains, also detected in the wild-type, are enriched in LTG mutants, and that LTG mutants are hypersusceptible to the production of diverse periplasmic polymers. Collectively, our results suggest that LTGs prevent toxic crowding of the periplasm with synthesis-derived peptidoglycan polymers and contrary to prevailing models, that this autolytic function can be temporally separate from peptidoglycan synthesis.

Data availability

All data generated or analyzed during this study are included in the manuscript and supporting files; Source Data files have been provided for Figures 1 and 3.

Article and author information

Author details

  1. Anna Isabell Weaver

    Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0556-0336
  2. Laura Alvarez

    Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, Umeå, Sweden
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2429-7542
  3. Kelly M Rosch

    Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6416-1730
  4. Asraa Ahmed

    Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Garrett Sean Wang

    Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Michael S vanNieuwenhze

    Department of Molecular and Cellular Biochemistry, Indiana University, Indiana, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. Felipe Cava

    The Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, Umeå, Sweden
    For correspondence
    felipe.cava@umu.se
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5995-718X
  8. Tobias Dörr

    Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, United States
    For correspondence
    tdoerr@cornell.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3283-9161

Funding

National Institutes of Health (R01-GM130971)

  • Tobias Dörr

Molecular Infection Medicine Sweden (MIMS2012)

  • Felipe Cava

Knut and Alice Wallenberg Foundation (KAW2012.0184)

  • Felipe Cava

Swedish Research Council (VR2018-02823)

  • Felipe Cava

Kempe Foundation (SMK2062)

  • Felipe Cava

National Institutes of Health (R01-GM113172)

  • Michael S vanNieuwenhze

National Institutes of Health (R35-GM136365)

  • Michael S vanNieuwenhze

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

Reviewing Editor

  1. Bavesh D Kana, University of the Witwatersrand, South Africa

Publication history

  1. Preprint posted: July 27, 2021 (view preprint)
  2. Received: August 19, 2021
  3. Accepted: January 23, 2022
  4. Accepted Manuscript published: January 24, 2022 (version 1)
  5. Version of Record published: February 7, 2022 (version 2)

Copyright

© 2022, Weaver 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. Anna Isabell Weaver
  2. Laura Alvarez
  3. Kelly M Rosch
  4. Asraa Ahmed
  5. Garrett Sean Wang
  6. Michael S vanNieuwenhze
  7. Felipe Cava
  8. Tobias Dörr
(2022)
Lytic transglycosylases mitigate periplasmic crowding by degrading soluble cell wall turnover products
eLife 11:e73178.
https://doi.org/10.7554/eLife.73178

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