Assembly principles of a unique cage formed by hexameric and decameric E. coli proteins

  1. Hélène Malet
  2. Kaiyin Liu
  3. Majida El Bakkourri
  4. Sze Wah Samuel Chan
  5. Gregory Effantin
  6. Maria Bacia
  7. Walid A Houry
  8. Irina Gutsche  Is a corresponding author
  1. CNRS, European Molecular Biology Laboratory, France
  2. University of Toronto, Canada
  3. CNRS, Université Grenoble Alpes, France
  4. CEA, CNRS, Université Grenoble Alpes, France

Abstract

A 3.3 MDa macromolecular cage between two E. coli proteins with seemingly incompatible symmetries - the hexameric AAA+ ATPase RavA and the decameric inducible lysine decarboxylase LdcI - is reconstructed by cryo-electron microscopy to 11 Å resolution. Combined with a 7.5 Å resolution reconstruction of the minimal complex between LdcI and the LdcI-binding domain of RavA, and the previously solved crystal structures of the individual components, this work enables to build a reliable pseudoatomic model of this unusual architecture and to identify conformational rearrangements and specific elements essential for complex formation. The design of the cage created via lateral interactions between five RavA rings is unique for the diverse AAA+ ATPase superfamily.

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Author details

  1. Hélène Malet

    CNRS, European Molecular Biology Laboratory, Grenoble, France
    Competing interests
    The authors declare that no competing interests exist.
  2. Kaiyin Liu

    University of Toronto, Toronto, Canada
    Competing interests
    The authors declare that no competing interests exist.
  3. Majida El Bakkourri

    University of Toronto, Toronto, Canada
    Competing interests
    The authors declare that no competing interests exist.
  4. Sze Wah Samuel Chan

    University of Toronto, Toronto, Canada
    Competing interests
    The authors declare that no competing interests exist.
  5. Gregory Effantin

    CNRS, Université Grenoble Alpes, Grenoble, France
    Competing interests
    The authors declare that no competing interests exist.
  6. Maria Bacia

    CEA, CNRS, Université Grenoble Alpes, Grenoble, France
    Competing interests
    The authors declare that no competing interests exist.
  7. Walid A Houry

    University of Toronto, Toronto, Canada
    Competing interests
    The authors declare that no competing interests exist.
  8. Irina Gutsche

    CNRS, Université Grenoble Alpes, Grenoble, France
    For correspondence
    gutsche@embl.fr
    Competing interests
    The authors declare that no competing interests exist.

Copyright

© 2014, Malet 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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https://doi.org/10.7554/eLife.03653

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