1. Microbiology and Infectious Disease

Maturing Mycobacterium smegmatis peptidoglycan requires non-canonical crosslinks to maintain shape

  1. Catherine Baranowski
  2. Michael A Welsh
  3. Lok-To Sham
  4. Haig A Eskandarian
  5. Hoong C Lim
  6. Karen J Kieser
  7. Jeffrey C Wagner
  8. John McKinney
  9. Georg E Fantner
  10. Thomas R Ioerger
  11. Suzanne Walker
  12. Thomas G Bernhardt
  13. Eric J Rubin  Is a corresponding author
  14. E Hesper Rego  Is a corresponding author
  1. Harvard TH Chan School of Public Health, United States
  2. Harvard Medical School, United States
  3. Swiss Federal Institute of Technology in Lausanne (EPFL), Switzerland
  4. Texas A&M University, United States
  5. Yale School of Medicine, United States
https://doi.org/10.7554/eLife.37516
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Cite this article
  1. Catherine Baranowski
  2. Michael A Welsh
  3. Lok-To Sham
  4. Haig A Eskandarian
  5. Hoong C Lim
  6. Karen J Kieser
  7. Jeffrey C Wagner
  8. John McKinney
  9. Georg E Fantner
  10. Thomas R Ioerger
  11. Suzanne Walker
  12. Thomas G Bernhardt
  13. Eric J Rubin
  14. E Hesper Rego
(2018)
Maturing Mycobacterium smegmatis peptidoglycan requires non-canonical crosslinks to maintain shape
eLife 7:e37516.
https://doi.org/10.7554/eLife.37516
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Abstract

In most well studied rod-shaped bacteria, peptidoglycan is primarily crosslinked by penicillin-binding proteins (PBPs). However, in mycobacteria, crosslinks formed by L,D-transpeptidases (LDTs) are highly abundant. To elucidate the role of these unusual crosslinks, we characterized Mycobacterium smegmatis cells lacking all LDTs. We find that crosslinks generate by LDTs are required for rod shape maintenance specifically at sites of aging cell wall, a byproduct of polar elongation. Asymmetric polar growth leads to a non-uniform distribution of these two types of crosslinks in a single cell. Consequently, in the absence of LDT-mediated crosslinks, PBP-catalyzed crosslinks become more important. Because of this, Mycobacterium tuberculosis (Mtb) is more rapidly killed using a combination of drugs capable of PBP- and LDT- inhibition. Thus, knowledge about the spatial and genetic relationship between drug targets can be exploited to more effectively treat this pathogen.

Data availability

Sequencing data were deposited into NCBI's Sequence Read Archive (SRA) under SRA study- SRP141343 https://www.ncbi.nlm.nih.gov/Traces/study/?acc=SRP141343

The following data sets were generated

Article and author information

Author details

  1. Catherine Baranowski

    Department of Immunology and Infectious Disease, Harvard TH Chan School of Public Health, Boston, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0407-8609

  2. Michael A Welsh

    Department of Microbiology and Immunobiology, Harvard Medical School, Boston, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8268-6285

  3. Lok-To Sham

    Department of Microbiology and Immunobiology, Harvard Medical School, Boston, United States
    Competing interests
    The authors declare that no competing interests exist.

  4. Haig A Eskandarian

    School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL), Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0610-0550

  5. Hoong C Lim

    Department of Microbiology and Immunobiology, Harvard Medical School, Boston, United States
    Competing interests
    The authors declare that no competing interests exist.

  6. Karen J Kieser

    Department of Immunology and Infectious Disease, Harvard TH Chan School of Public Health, Boston, United States
    Competing interests
    The authors declare that no competing interests exist.

  7. Jeffrey C Wagner

    Department of Immunology and Infectious Disease, Harvard TH Chan School of Public Health, Boston, United States
    Competing interests
    The authors declare that no competing interests exist.

  8. John McKinney

    School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL), Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.

  9. Georg E Fantner

    School of Engineering, Swiss Federal Institute of Technology in Lausanne (EPFL), Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.

  10. Thomas R Ioerger

    Department of Computer Science and Engineering, Texas A&M University, College Station, United States
    Competing interests
    The authors declare that no competing interests exist.

  11. Suzanne Walker

    Department of Microbiology and Immunobiology, Harvard Medical School, Boston, United States
    Competing interests
    The authors declare that no competing interests exist.

  12. Thomas G Bernhardt

    Department of Microbiology and Immunobiology, Harvard Medical School, Boston, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3566-7756

  13. Eric J Rubin

    Department of Immunology and Infectious Disease, Harvard TH Chan School of Public Health, Boston, United States
    For correspondence
    erubin@hsph.harvard.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5120-962X

  14. E Hesper Rego

    Department of Microbial Pathogenesis, Yale School of Medicine, New Haven, United States
    For correspondence
    hesper.rego@yale.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2973-8354

Funding

National Institutes of Health (U19 AI107774)

  • Thomas R Ioerger
  • Eric J Rubin

National Institutes of Health (R01 GM76710)

  • Suzanne Walker

National Institutes of Health (R01AI083365)

  • Thomas G Bernhardt

National Institutes of Health (F32GM123579)

  • Michael A Welsh

Swiss National Science Foundation (205321_134786)

  • Georg E Fantner

Innovative Medicines Initiative (115337)

  • John McKinney

EU-FP7/Eurostars (E!8213)

  • Georg E Fantner

European Molecular Biology Organization (750-2016)

  • Haig A Eskandarian

National Science Foundation (DGE0946799)

  • Karen J Kieser

National Institutes of Health (U19AI109764)

  • Thomas G Bernhardt

Swiss National Science Foundation (205320_152675)

  • Georg E Fantner

Burroughs Wellcome Fund (Career Award at the Scientific Interface)

  • E Hesper Rego

American Heart Association (14POST18480014)

  • Lok-To Sham

Simons Foundation (Fellow of the Life Sciences Research Foundation Award)

  • Hoong C Lim

Swiss National Science Foundation (310030_156945)

  • John McKinney

European Union (FP7/2007-2013/ERC Grant agreement No. 307338 (NaMic))

  • Georg E Fantner

European Molecular Biology Organization (191-2014)

  • Haig A Eskandarian

National Science Foundation (DGE1144152)

  • Karen J Kieser

National Institutes of Health (F32AI104287)

  • E Hesper Rego

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. Received: April 12, 2018
  2. Accepted: October 11, 2018
  3. Accepted Manuscript published: October 16, 2018 (version 1)
  4. Version of Record published: November 12, 2018 (version 2)
  5. Version of Record updated: September 5, 2019 (version 3)

Copyright

© 2018, Baranowski 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. Catherine Baranowski
  2. Michael A Welsh
  3. Lok-To Sham
  4. Haig A Eskandarian
  5. Hoong C Lim
  6. Karen J Kieser
  7. Jeffrey C Wagner
  8. John McKinney
  9. Georg E Fantner
  10. Thomas R Ioerger
  11. Suzanne Walker
  12. Thomas G Bernhardt
  13. Eric J Rubin
  14. E Hesper Rego
(2018)
Maturing Mycobacterium smegmatis peptidoglycan requires non-canonical crosslinks to maintain shape
eLife 7:e37516.
https://doi.org/10.7554/eLife.37516

Categories and tags

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