Adaptation of the periplasm to maintain spatial constraints essential for cell envelope processes and cell viability

  1. Eric Mandela
  2. Christopher J Stubenrauch
  3. David Ryoo
  4. Hyea Hwang
  5. Eli J Cohen
  6. Von Vergel L Torres
  7. Pankaj Deo
  8. Chaille T Webb
  9. Cheng Huang
  10. Ralf B Schittenhelm
  11. Morgan Beeby
  12. James C Gumbart  Is a corresponding author
  13. Trevor Lithgow  Is a corresponding author
  14. Iain D Hay  Is a corresponding author
  1. Monash University, Australia
  2. Georgia Institute of Technology, United States
  3. Imperial College London, United Kingdom
  4. The University of Auckland, New Zealand

Abstract

The cell envelope of Gram-negative bacteria consists of two membranes surrounding a periplasm and peptidoglycan layer. Molecular machines spanning the cell envelope depend on spatial constraints and load-bearing forces across the cell envelope and surface. The mechanisms dictating spatial constraints across the cell envelope remain incompletely defined. In Escherichia coli, the coiled-coil lipoprotein Lpp contributes the only covalent linkage between the outer membrane and the underlying peptidoglycan layer. Using proteomics, molecular dynamics and a synthetic lethal screen we show that lengthening Lpp to the upper limit does not change the spatial constraint, but is accommodated by other factors which thereby become essential for viability. Our findings demonstrate E. coli expressing elongated Lpp does not simply enlarge the periplasm in response, but the bacteria accommodate by a combination of tilting Lpp and reducing the amount of the covalent bridge. By genetic screening we identified all of the genes in E. coli that become essential in order to enact this adaptation, and by quantitative proteomics discovered that very few proteins need to be up- or down-regulated in steady-state levels in order to accommodate the longer Lpp. We observed increased levels of factors determining cell stiffness, a decrease in membrane integrity, an increase membrane vesiculation and a dependance on otherwise non-essential tethers to maintain lipid transport and peptidoglycan biosynthesis. Further this has implications for understanding how spatial constraint across the envelope controls processes such as flagellum-driven motility, cellular signaling and protein translocation.

Data availability

All data generated from this study is supplied in the relevant supplemental files

Article and author information

Author details

  1. Eric Mandela

    Department of Microbiology, Monash University, Clayton, Victoria, Australia
    Competing interests
    The authors declare that no competing interests exist.
  2. Christopher J Stubenrauch

    Department of Microbiology, Monash University, Clayton, Victoria, Australia
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4388-3184
  3. David Ryoo

    Interdisciplinary Bioengineering Graduate Program, Georgia Institute of Technology, Atlanta, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Hyea Hwang

    School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Eli J Cohen

    Department of Life Sciences, Imperial College London, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  6. Von Vergel L Torres

    Department of Microbiology, Monash University, Clayton, Victoria, Australia
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3387-1112
  7. Pankaj Deo

    Department of Microbiology, Monash University, Clayton, Victoria, Australia
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6947-5317
  8. Chaille T Webb

    Department of Microbiology, Monash University, Clayton, Victoria, Australia
    Competing interests
    The authors declare that no competing interests exist.
  9. Cheng Huang

    Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia
    Competing interests
    The authors declare that no competing interests exist.
  10. Ralf B Schittenhelm

    Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia
    Competing interests
    The authors declare that no competing interests exist.
  11. Morgan Beeby

    Department of Life Sciencesa, Imperial College London, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-6413-9835
  12. James C Gumbart

    School of Physics, Georgia Institute of Technology, Atlanta, United States
    For correspondence
    gumbart@physics.gatech.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1510-7842
  13. Trevor Lithgow

    Department of Microbiology, Monash University, Melbourne, Australia
    For correspondence
    trevor.lithgow@monash.edu
    Competing interests
    The authors declare that no competing interests exist.
  14. Iain D Hay

    School of Biological Sciences, The University of Auckland, Auckland, New Zealand
    For correspondence
    iain.hay@auckland.ac.nz
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8797-6038

Funding

Australian Research Council (FL130100038)

  • Trevor Lithgow
  • Iain D Hay

United States National Institute of Health (R01-GM123169)

  • James C Gumbart

United States National Institute of Health (R01-AI052293)

  • James C Gumbart

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

Copyright

© 2022, Mandela 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. Eric Mandela
  2. Christopher J Stubenrauch
  3. David Ryoo
  4. Hyea Hwang
  5. Eli J Cohen
  6. Von Vergel L Torres
  7. Pankaj Deo
  8. Chaille T Webb
  9. Cheng Huang
  10. Ralf B Schittenhelm
  11. Morgan Beeby
  12. James C Gumbart
  13. Trevor Lithgow
  14. Iain D Hay
(2022)
Adaptation of the periplasm to maintain spatial constraints essential for cell envelope processes and cell viability
eLife 11:e73516.
https://doi.org/10.7554/eLife.73516

Share this article

https://doi.org/10.7554/eLife.73516

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