Host-induced bacterial cell wall decomposition mediates pattern-triggered immunity in Arabidopsis

Abstract

Peptidoglycans (PGN) are immunogenic bacterial surface patterns that trigger immune activation in metazoans and plants. It is generally unknown, how complex bacterial structures, such as PGN, are perceived by plant pattern recognition receptors (PRR) and whether host hydrolytic activities facilitate decomposition of bacterial matrices and generation of soluble PRR ligands. Here, we show that Arabidopsis thaliana upon bacterial infection or exposure to microbial patterns produces a metazoan lysozyme-like hydrolase (lysozyme 1, LYS1). LYS1 activity releases soluble PGN fragments from insoluble bacterial cell walls and cleavage products are able to trigger responses typically associated with plant immunity. Importantly, LYS1 mutant genotypes exhibit super-susceptibility to bacterial infections similar to that observed on PGN receptor mutants. We propose that plants employ hydrolytic activities for the decomposition of complex bacterial structures, and that soluble pattern generation might aid PRR-mediated immune activation in cell layers adjacent to infection sites.

Article and author information

Author details

  1. Xiaokun Liu

    University of Tübingen, Tübingen, Germany
    Competing interests
    No competing interests declared.
  2. Heini M Grabherr

    University of Tübingen, Tübingen, Germany
    Competing interests
    No competing interests declared.
  3. Roland Willmann

    University of Tübingen, Tübingen, Germany
    Competing interests
    No competing interests declared.
  4. Dagmar Kolb

    University of Tübingen, Tübingen, Germany
    Competing interests
    No competing interests declared.
  5. Frédéric Brunner

    University of Tübingen, Tübingen, Germany
    Competing interests
    No competing interests declared.
  6. Ute Bertsche

    University of Tübingen, Tübingen, Germany
    Competing interests
    No competing interests declared.
  7. Daniel Kühner

    University of Tübingen, Tübingen, Germany
    Competing interests
    No competing interests declared.
  8. Mirita Franz-Wachtel

    University of Tübingen, Tübingen, Germany
    Competing interests
    No competing interests declared.
  9. Bushra Amin

    University of Tübingen, Tübingen, Germany
    Competing interests
    No competing interests declared.
  10. Georg Felix

    University of Tübingen, Tübingen, Germany
    Competing interests
    No competing interests declared.
  11. Marc Ongena

    University of Liege-Gembloux Agro-Bio Tech, Gembloux, Belgium
    Competing interests
    No competing interests declared.
  12. Thorsten Nürnberger

    University of Tübingen, Tübingen, Germany
    Competing interests
    Thorsten Nürnberger, Reviewing editor, eLife.
  13. Andrea A Gust

    University of Tübingen, Tübingen, Germany
    For correspondence
    andrea.gust@zmbp.uni-tuebingen.de
    Competing interests
    No competing interests declared.

Copyright

© 2014, Liu 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. Xiaokun Liu
  2. Heini M Grabherr
  3. Roland Willmann
  4. Dagmar Kolb
  5. Frédéric Brunner
  6. Ute Bertsche
  7. Daniel Kühner
  8. Mirita Franz-Wachtel
  9. Bushra Amin
  10. Georg Felix
  11. Marc Ongena
  12. Thorsten Nürnberger
  13. Andrea A Gust
(2014)
Host-induced bacterial cell wall decomposition mediates pattern-triggered immunity in Arabidopsis
eLife 3:e01990.
https://doi.org/10.7554/eLife.01990

Share this article

https://doi.org/10.7554/eLife.01990

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