Distinct regions of H. pylori's bactofilin CcmA regulate protein-protein interactions to control helical cell shape

  1. Sophie R Sichel
  2. Benjamin P Bratton
  3. Nina Reda Salama  Is a corresponding author
  1. Fred Hutchinson Cancer Research Center, United States
  2. Vanderbilt University Medical Center, United States

Abstract

The helical shape of H. pylori cells promotes robust stomach colonization, however, how the helical shape of H. pylori cells is determined is unresolved. Previous work identified helical-cell-shape-promoting protein complexes containing a peptidoglycan-hydrolase (Csd1), a peptidoglycan precursor synthesis enzyme (MurF), a non-enzymatic homologue of Csd1 (Csd2), non-enzymatic transmembrane proteins (Csd5 and Csd7), and a bactofilin (CcmA). Bactofilins are highly conserved, spontaneously polymerizing cytoskeletal bacterial proteins. We sought to understand CcmA's function in generating the helical shape of H. pylori cells. Using CcmA deletion analysis, in vitro polymerization, and in vivo co-immunoprecipitation experiments we identified that the bactofilin domain and N-terminal region of CcmA are required for helical cell shape and the bactofilin domain of CcmA is sufficient for polymerization and interactions with Csd5 and Csd7. We also found that CcmA's N-terminal region inhibits interaction with Csd7. Deleting the N-terminal region of CcmA increases CcmA-Csd7 interactions and destabilizes the peptidoglycan-hydrolase Csd1. Using super-resolution microscopy, we found that Csd5 recruits CcmA to the cell envelope and promotes CcmA enrichment at the major helical axis. Thus, CcmA helps organize cell-shape-determining proteins and peptidoglycan synthesis machinery to coordinate cell wall modification and synthesis, promoting the curvature required to build a helical cell.

Data availability

Data generated or analysed during this study are included in the manuscript and supporting file; Source Data files have been provided for Figures 2, 5, 6 and 7.Microscopy data are available at BioImage Archive and accession code is S-BIAD462

The following data sets were generated

Article and author information

Author details

  1. Sophie R Sichel

    Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Benjamin P Bratton

    Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1128-2560
  3. Nina Reda Salama

    Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, United States
    For correspondence
    nsalama@fredhutch.org
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2762-1424

Funding

National Institute of Allergy and Infectious Diseases (F31 AI152331)

  • Sophie R Sichel

National Institute of Allergy and Infectious Diseases (R01 AI136946)

  • Nina Reda Salama

National Institute of General Medical Sciences (T32 GM95421)

  • Sophie R Sichel

GO-MAP Graduat Opportunity Program Research Assistantship Award (Sophie Sichel)

  • Sophie R Sichel

VUMC Discovery Scholars in Health and Medicine Program (Benjamin Bratton)

  • Benjamin P Bratton

National Cancer Institute (P31 CA015704)

  • Nina Reda Salama

Audacious Project (Institute for Protein Design)

  • Sophie R Sichel

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: April 5, 2022 (view preprint)
  2. Received: May 9, 2022
  3. Accepted: September 7, 2022
  4. Accepted Manuscript published: September 8, 2022 (version 1)
  5. Version of Record published: September 23, 2022 (version 2)

Copyright

© 2022, Sichel 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. Sophie R Sichel
  2. Benjamin P Bratton
  3. Nina Reda Salama
(2022)
Distinct regions of H. pylori's bactofilin CcmA regulate protein-protein interactions to control helical cell shape
eLife 11:e80111.
https://doi.org/10.7554/eLife.80111

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