1. Microbiology and Infectious Disease
  2. Structural Biology and Molecular Biophysics
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Asymmetric localization of the cell division machinery during Bacillus subtilis sporulation

  1. Kanika Khanna
  2. Javier Lopez Garrido
  3. Joseph Sugie
  4. Kit Pogliano  Is a corresponding author
  5. Elizabeth Villa  Is a corresponding author
  1. University of California, San Diego, United States
Research Article
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Cite this article as: eLife 2021;10:e62204 doi: 10.7554/eLife.62204

Abstract

The Gram-positive bacterium Bacillus subtilis can divide via two modes. During vegetative growth, the division septum is formed at the midcell to produce two equal daughter cells. However, during sporulation, the division septum is formed closer to one pole to yield a smaller forespore and a larger mother cell. Using cryo-electron tomography, genetics and fluorescence microscopy, we found that the organization of the division machinery is different in the two septa. While FtsAZ filaments, the major orchestrators of bacterial cell division, are present uniformly around the leading edge of the invaginating vegetative septa, they are only present on the mother cell side of the invaginating sporulation septa. We provide evidence suggesting that the different distribution and number of FtsAZ filaments impact septal thickness, causing vegetative septa to be thicker than sporulation septa already during constriction. Finally, we show that a sporulation-specific protein, SpoIIE, regulates asymmetric divisome localization and septal thickness during sporulation.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files. Additionally, we have deposited representative tomograms for each growth condition in the Electron Microscopy Data Bank (EMDB) accession codes EMD-23963, EMD-23964, EMD-23965, EMD-23966, EMD-23967 and EMD-23968, and tilt series in the Electron Microscopy Public Image Archive (EMPIAR) database accession code EMPIAR-10710.

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Author details

  1. Kanika Khanna

    Division of Biological Sciences, University of California, San Diego, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7150-0350
  2. Javier Lopez Garrido

    Division of Biological Sciences, University of California, San Diego, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Joseph Sugie

    Division of Biological Sciences, University of California, San Diego, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2911-1807
  4. Kit Pogliano

    Division of Biological Sciences, University of California, San Diego, La Jolla, United States
    For correspondence
    kpogliano@ucsd.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7868-3345
  5. Elizabeth Villa

    Division of Biological Sciences, University of California, San Diego, La Jolla, United States
    For correspondence
    evilla@ucsd.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4677-9809

Funding

National Institutes of Health (R01-GM057045)

  • Kit Pogliano
  • Elizabeth Villa

National Science Foundation (DBI 1920374)

  • Elizabeth Villa

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication. We acknowledge the use of San Diego Nanotechnology Infrastructure (SDNI) of UC San Diego, a member of the National Nanotechnology Coordinated Infrastructure, supported by the NSF grant ECCS-1542148. Please note it was not possible to add this to the above above Funders tab as it was not awarded to an author.

Reviewing Editor

  1. Michael T Laub, Massachusetts Institute of Technology, United States

Publication history

  1. Received: August 17, 2020
  2. Accepted: May 10, 2021
  3. Accepted Manuscript published: May 21, 2021 (version 1)
  4. Version of Record published: June 10, 2021 (version 2)

Copyright

© 2021, Khanna 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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