The mycobacterial ImuA'-ImuB-DnaE2 mutasome: composition and recruitment in live cells

  1. Sophia Gessner
  2. Zela Alexandria-Mae Martin
  3. Michael Anton Reiche
  4. Joana A Santos
  5. Ryan Dinkele
  6. Atondaho Ramudzuli
  7. Neeraj Dhar
  8. Timothy J de Wet
  9. Saber Anoosheh
  10. Dirk M Lang
  11. Jesse Arron
  12. Teng Leong Chew
  13. Jennifer Herrmann
  14. Rolf Müller
  15. John D McKinney
  16. Roger Woodgate
  17. Valerie Mizrahi
  18. Česlovas Venclovas
  19. Meindert Hugo Lamers
  20. Digby F Warner  Is a corresponding author
  1. University of Cape Town, South Africa
  2. Howard Hughes Medical Institute, United States
  3. Leiden University Medical Center, Netherlands
  4. University of Saskatchewan, Canada
  5. Umeå University, Sweden
  6. Helmholtz Institute for Pharmaceutical Research Saarland, Germany
  7. Swiss Federal Institute of Technology in Lausanne, Switzerland
  8. Eunice Kennedy Shriver National Institute of Child Health and Human Development, United States
  9. Vilnius University, Lithuania

Abstract

A DNA damage-inducible mutagenic gene cassette has been implicated in the emergence of drug resistance in Mycobacterium tuberculosis during anti-tuberculosis (TB) chemotherapy. However, the molecular composition and operation of the encoded 'mycobacterial mutasome' - minimally comprising DnaE2 polymerase and ImuA′ and ImuB accessory proteins - remain elusive. Following exposure of mycobacteria to DNA damaging agents, we observe that DnaE2 and ImuB co-localize with the DNA polymerase III β subunit (β clamp) in distinct intracellular foci. Notably, genetic inactivation of the mutasome in an imuBAAAAGG mutant containing a disrupted β clamp-binding motif abolishes ImuB-β clamp focus formation, a phenotype recapitulated pharmacologically by treating bacilli with griselimycin and in biochemical assays in which this β clamp-binding antibiotic collapses pre-formed ImuB-β clamp complexes. These observations establish the essentiality of the ImuB-β clamp interaction for mutagenic DNA repair in mycobacteria, identifying the mutasome as target for adjunctive therapeutics designed to protect anti-TB drugs against emerging resistance.

Data availability

Source data for all figures contained in the manuscript and SI have been deposited in Dryad; see https://datadryad.org/stash/share/fjhwiXFEIIM5-6liMtXIQn0Ehq4NIKZ3690FiR8lWyI.

The following data sets were generated

Article and author information

Author details

  1. Sophia Gessner

    Department of Pathology, University of Cape Town, Cape Town, South Africa
    Competing interests
    The authors declare that no competing interests exist.
  2. Zela Alexandria-Mae Martin

    Department of Pathology, University of Cape Town, Cape Town, South Africa
    Competing interests
    The authors declare that no competing interests exist.
  3. Michael Anton Reiche

    Advanced Imaging Center, Howard Hughes Medical Institute, Ashburn, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Joana A Santos

    Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, Netherlands
    Competing interests
    The authors declare that no competing interests exist.
  5. Ryan Dinkele

    Department of Pathology, University of Cape Town, Cape Town, South Africa
    Competing interests
    The authors declare that no competing interests exist.
  6. Atondaho Ramudzuli

    Department of Pathology, University of Cape Town, Cape Town, South Africa
    Competing interests
    The authors declare that no competing interests exist.
  7. Neeraj Dhar

    Vaccine and Infectious Disease Organization, University of Saskatchewan, Saskatoon, Canada
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5887-8137
  8. Timothy J de Wet

    Department of Pathology, University of Cape Town, Cape Town, South Africa
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3978-5322
  9. Saber Anoosheh

    Department of Chemistry, Umeå University, Umeå, Sweden
    Competing interests
    The authors declare that no competing interests exist.
  10. Dirk M Lang

    Department of Human Biology, University of Cape Town, Cape Town, South Africa
    Competing interests
    The authors declare that no competing interests exist.
  11. Jesse Arron

    Advanced Imaging Center, Howard Hughes Medical Institute, Ashburn, United States
    Competing interests
    The authors declare that no competing interests exist.
  12. Teng Leong Chew

    Advanced Imaging Center, Howard Hughes Medical Institute, Ashburn, United States
    Competing interests
    The authors declare that no competing interests exist.
  13. Jennifer Herrmann

    Helmholtz Centre for Infection Research, Helmholtz Institute for Pharmaceutical Research Saarland, Saarbrücken, Germany
    Competing interests
    The authors declare that no competing interests exist.
  14. Rolf Müller

    Helmholtz Centre for Infection Research, Helmholtz Institute for Pharmaceutical Research Saarland, Saarbrucken, Germany
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1042-5665
  15. John D McKinney

    School of Life Sciences, Swiss Federal Institute of Technology in Lausanne, Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0557-3479
  16. Roger Woodgate

    Laboratory of Genomic Integrity, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5581-4616
  17. Valerie Mizrahi

    Department of Pathology, University of Cape Town, Cape Town, South Africa
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4824-9115
  18. Česlovas Venclovas

    Institute of Biotechnology, Vilnius University, Vilnius, Lithuania
    Competing interests
    The authors declare that no competing interests exist.
  19. Meindert Hugo Lamers

    Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, Netherlands
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4205-1338
  20. Digby F Warner

    Department of Pathology, University of Cape Town, Cape Town, South Africa
    For correspondence
    digby.warner@uct.ac.za
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4146-0930

Funding

Eunice Kennedy Shriver National Institute of Child Health and Human Development (U01HD085531)

  • Roger Woodgate
  • Digby F Warner

Norges Forskningsråd (261669)

  • Digby F Warner

South African Medical Research Council (SHIP and Extramural Unit)

  • Valerie Mizrahi
  • Digby F Warner

National Research Foundation

  • Valerie Mizrahi
  • Digby F Warner

Howard Hughes Medical Institute (Senior International Research Scholars)

  • Valerie Mizrahi

Leids Universitair Medisch Centrum (LUMC Fellowship)

  • Meindert Hugo Lamers

National Research Foundation (104683)

  • Michael Anton Reiche

David and Elaine Potter Foundation (PhD Fellowship)

  • Zela Alexandria-Mae Martin

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

Reviewing Editor

  1. Christina L Stallings, Washington University School of Medicine, United States

Version history

  1. Received: November 16, 2021
  2. Preprint posted: November 17, 2021 (view preprint)
  3. Accepted: August 1, 2023
  4. Accepted Manuscript published: August 2, 2023 (version 1)
  5. Version of Record published: August 11, 2023 (version 2)

Copyright

This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.

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  1. Sophia Gessner
  2. Zela Alexandria-Mae Martin
  3. Michael Anton Reiche
  4. Joana A Santos
  5. Ryan Dinkele
  6. Atondaho Ramudzuli
  7. Neeraj Dhar
  8. Timothy J de Wet
  9. Saber Anoosheh
  10. Dirk M Lang
  11. Jesse Arron
  12. Teng Leong Chew
  13. Jennifer Herrmann
  14. Rolf Müller
  15. John D McKinney
  16. Roger Woodgate
  17. Valerie Mizrahi
  18. Česlovas Venclovas
  19. Meindert Hugo Lamers
  20. Digby F Warner
(2023)
The mycobacterial ImuA'-ImuB-DnaE2 mutasome: composition and recruitment in live cells
eLife 12:e75628.
https://doi.org/10.7554/eLife.75628

Share this article

https://doi.org/10.7554/eLife.75628

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