1. Genetics and Genomics
  2. Plant Biology
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A gene horizontally transferred from bacteria protects arthropods from host plant cyanide poisoning

  1. Nicky Wybouw
  2. Wannes Dermauw
  3. Luc Tirry
  4. Christian Stevens
  5. Miodrag Grbić
  6. René Feyereisen
  7. Thomas Van Leeuwen  Is a corresponding author
  1. Ghent University, Belgium
  2. University of Western Ontario, Canada
  3. Centre National de la Recherche Scientifique and Université de Nice Sophia Antipolis, France
  4. University of Amsterdam, Netherlands
Research Article
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Cite this article as: eLife 2014;3:e02365 doi: 10.7554/eLife.02365

Abstract

Cyanogenic glucosides are among the most widespread defense chemicals of plants. Upon plant tissue disruption, these glucosides are hydrolyzed to a reactive hydroxynitrile that releases toxic hydrogen cyanide (HCN). Yet many mite and lepidopteran species can thrive on plants defended by cyanogenic glucosides. The nature of the enzyme known to detoxify HCN to β-cyanoalanine in arthropods has remained enigmatic. Here we identify this enzyme by transcriptome analysis and functional expression. Phylogenetic analysis showed that the gene is a member of the cysteine synthase family horizontally transferred from bacteria to phytophagous mites and Lepidoptera. The recombinant mite enzyme had both β-cyanoalanine synthase and cysteine synthase activity but enzyme kinetics showed that cyanide detoxification activity was strongly favored. Our results therefore suggest that an ancient horizontal transfer of a gene originally involved in sulfur amino acid biosynthesis in bacteria was co-opted by herbivorous arthropods to detoxify plant produced cyanide.

Article and author information

Author details

  1. Nicky Wybouw

    Ghent University, Ghent, Belgium
    Competing interests
    The authors declare that no competing interests exist.
  2. Wannes Dermauw

    Ghent University, Ghent, Belgium
    Competing interests
    The authors declare that no competing interests exist.
  3. Luc Tirry

    Ghent University, Ghent, Belgium
    Competing interests
    The authors declare that no competing interests exist.
  4. Christian Stevens

    Ghent University, Ghent, Belgium
    Competing interests
    The authors declare that no competing interests exist.
  5. Miodrag Grbić

    University of Western Ontario, London, Canada
    Competing interests
    The authors declare that no competing interests exist.
  6. René Feyereisen

    Centre National de la Recherche Scientifique and Université de Nice Sophia Antipolis, Nice, France
    Competing interests
    The authors declare that no competing interests exist.
  7. Thomas Van Leeuwen

    University of Amsterdam, Amsterdam, Netherlands
    For correspondence
    thomas.vanleeuwen@ugent.be
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Joerg Bohlmann, University of British Columbia, Canada

Publication history

  1. Received: January 22, 2014
  2. Accepted: April 1, 2014
  3. Accepted Manuscript published: April 24, 2014 (version 1)
  4. Version of Record published: May 6, 2014 (version 2)

Copyright

© 2014, Wybouw et al.

This article is distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use and redistribution provided that the original author and source are credited.

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