Defective lytic transglycosylase disrupts cell morphogenesis by hindering cell wall de-O-acetylation in N. meningitidis

Abstract

Lytic transglycosylases (LT) are enzymes involved in peptidoglycan (PG) remodeling. However, their contribution to cell wall-modifying complexes and their potential as antimicrobial drug targets remain unclear. Here, we determined a high-resolution structure of the LT, an outer membrane lipoprotein from Neisseria species with a disordered active site helix (alpha helix 30). We show that deletion of the conserved alpha-helix 30 interferes with the integrity of the cell wall, disrupts cell division, cell separation, and impairs the fitness of the human pathogen Neisseria meningitidis during infection. Additionally, deletion of alpha-helix 30 results in hyperacetylated PG, suggesting this LtgA variant affects the function of the PG de-O-acetylase (Ape 1). Our study revealed that Ape 1 requires LtgA for optimal function, demonstrating that LTs can modulate the activity of their protein-binding partner. We show that targeting specific domains in LTs can be lethal, which opens the possibility that LTs are useful drug-targets.

Data availability

Data Availability: Coordinates and structural data have been submitted to the Protein Data Bank under the accession code 6H5F.

The following data sets were generated

Article and author information

Author details

  1. Allison Hillary Williams

    Unité Biologie et Génétique de la Paroi Bactérienne, Institut Pasteur, Paris, France
    For correspondence
    awilliam@pasteur.fr
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0726-141X
  2. Richard Wheeler

    Unité Biologie et Génétique de la Paroi Bactérienne, Institut Pasteur, Paris, France
    Competing interests
    The authors declare that no competing interests exist.
  3. Ala-Eddine Deghmane

    Unité des Infection Bactériennes Invasives, Institut Pasteur, Paris, France
    Competing interests
    The authors declare that no competing interests exist.
  4. Ignacio Santecchia

    Unité Biologie et Génétique de la Paroi Bactérienne, Institut Pasteur, Paris, France
    Competing interests
    The authors declare that no competing interests exist.
  5. Ryan E Schaub

    Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Samia Hicham

    Unité Biologie et Génétique de la Paroi Bactérienne, Institut Pasteur, Paris, France
    Competing interests
    The authors declare that no competing interests exist.
  7. Maryse Moya Nilges

    Unité Technologie et Service BioImagerie Ultrastructural, Institut Pasteur, Paris, France
    Competing interests
    The authors declare that no competing interests exist.
  8. Christian Malosse

    Unité Technologie et Service Spectrométrie de Masse pour la Biologie, Institut Pasteur, Paris, France
    Competing interests
    The authors declare that no competing interests exist.
  9. Julia Chamot-Rooke

    Unité Technologie et Service Spectrométrie de Masse pour la Biologie, Institut Pasteur, Paris, France
    Competing interests
    The authors declare that no competing interests exist.
  10. Ahmed Haouz

    Plate-forme de Cristallographie, Institut Pasteur, Paris, France
    Competing interests
    The authors declare that no competing interests exist.
  11. Joseph P Dillard

    Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, United States
    Competing interests
    The authors declare that no competing interests exist.
  12. William P Robins

    Department of Microbiology, Harvard Medical School, Boston, United States
    Competing interests
    The authors declare that no competing interests exist.
  13. Muhamed-Kheir Taha

    Unité des Infection Bactériennes Invasives, Institut Pasteur, Paris, France
    Competing interests
    The authors declare that no competing interests exist.
  14. Ivo Gomperts Boneca

    Unité Biologie et Génétique de la Paroi Bactérienne, Institut Pasteur, Paris, France
    For correspondence
    bonecai@pasteur.fr
    Competing interests
    The authors declare that no competing interests exist.

Funding

European Molecular Biology Organization (ALTF 732-2010)

  • Allison Hillary Williams

European Research Council (PGN from SHAPE to VIR 202283)

  • Ivo Gomperts Boneca

Fondation pour la Recherche Médicale (DBF20160635726)

  • Ivo Gomperts Boneca

Institut Carnot-Pasteur (Maladies Infectious fellowship)

  • Allison Hillary Williams

Institut Carnot Pasteur Microbes and Sante

  • Ignacio Santecchia

Fondation pour la Recherche Médicale (FDT201805005258)

  • Ignacio Santecchia

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

Ethics

Animal experimentation: Animal work in this study was carried out at the Institut Pasteur in strict accordance with the European Union Directive 2010/63/EU (and its revision 86/609/EEC) on the protection of animals used for scientific purposes. The laboratory at the Institut Pasteur has the administrative authorization for animal experimentation (Permit Number 75-1554) and the protocol was approved by the Institut Pasteur Review Board that is part of the Regional Committee of Ethics of Animal Experiments of Paris Region (Permit Number: 99-174). All the invasive procedures were performed under anesthesia and all possible efforts were made to minimize animal suffering.

Version history

  1. Received: August 21, 2019
  2. Accepted: February 4, 2020
  3. Accepted Manuscript published: February 5, 2020 (version 1)
  4. Version of Record published: March 20, 2020 (version 2)

Copyright

© 2020, Williams 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. Allison Hillary Williams
  2. Richard Wheeler
  3. Ala-Eddine Deghmane
  4. Ignacio Santecchia
  5. Ryan E Schaub
  6. Samia Hicham
  7. Maryse Moya Nilges
  8. Christian Malosse
  9. Julia Chamot-Rooke
  10. Ahmed Haouz
  11. Joseph P Dillard
  12. William P Robins
  13. Muhamed-Kheir Taha
  14. Ivo Gomperts Boneca
(2020)
Defective lytic transglycosylase disrupts cell morphogenesis by hindering cell wall de-O-acetylation in N. meningitidis
eLife 9:e51247.
https://doi.org/10.7554/eLife.51247

Share this article

https://doi.org/10.7554/eLife.51247

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