Stepwise visualization of membrane pore formation by suilysin, a bacterial cholesterol-dependent cytolysin

Abstract

Membrane attack complex/perforin/cholesterol-dependent cytolysin (MACPF/CDC) proteins constitute a major superfamily of pore-forming proteins that act as bacterial virulence factors and effectors in immune defence. Upon binding to the membrane, they convert from the soluble monomeric form to oligomeric, membrane-inserted pores. Using real-time atomic force microscopy (AFM), electron microscopy (EM) and atomic structure fitting, we have mapped the structure and assembly pathways of a bacterial CDC in unprecedented detail and accuracy, focussing on suilysin from Streptococcus suis. We show that suilysin assembly is a noncooperative process that is terminated before the protein inserts into the membrane. The resulting ring-shaped pores and kinetically trapped arc-shaped assemblies are all seen to perforate the membrane, as also visible by the ejection of its lipids. Membrane insertion requires a concerted conformational change of the monomeric subunits, with a marked expansion in pore diameter due to large changes in subunit structure and packing.

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Author details

  1. Carl Leung

    London Centre for Nanotechnology, University College London, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  2. Natalya V Dudkina

    Department of Crystallography, Birkbeck College, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  3. Natalya Lukoyanova

    Department of Crystallography, Birkbeck College, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  4. Adrian W Hodel

    London Centre for Nanotechnology, University College London, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  5. Irene Farabella

    Department of Crystallography, Birkbeck College, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  6. Arun P Pandurangan

    Department of Crystallography, Birkbeck College, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  7. Nasrin Jahan

    Department of Infection, Immunity, and Inflammation, University of Leicester, Leicester, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  8. Mafalda Pires Damaso

    Department of Infection, Immunity, and Inflammation, University of Leicester, Leicester, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  9. Dino Osmanović

    London Centre for Nanotechnology, University College London, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  10. Cyril F Reboul

    Department of Biochemistry and Molecular Biology, Monash University, Melbourne, Australia
    Competing interests
    The authors declare that no competing interests exist.
  11. Michelle A Dunstone

    Department of Biochemistry and Molecular Biology, Monash University, Melbourne, Australia
    Competing interests
    The authors declare that no competing interests exist.
  12. Peter W Andrew

    Department of Infection, Immunity, and Inflammation, University of Leicester, Leicester, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  13. Rana Lonnen

    Department of Infection, Immunity, and Inflammation, University of Leicester, Leicester, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  14. Maya Topf

    Department of Crystallography, Birkbeck College, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  15. Helen R Saibil

    Department of Crystallography, Birkbeck College, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  16. Bart W Hoogenboom

    London Centre for Nanotechnology, University College London, London, United Kingdom
    For correspondence
    b.hoogenboom@ucl.ac.uk
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Volker Dötsch, Goethe University, Germany

Version history

  1. Received: August 5, 2014
  2. Accepted: November 24, 2014
  3. Accepted Manuscript published: December 2, 2014 (version 1)
  4. Version of Record published: December 24, 2014 (version 2)

Copyright

© 2014, Leung 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. Carl Leung
  2. Natalya V Dudkina
  3. Natalya Lukoyanova
  4. Adrian W Hodel
  5. Irene Farabella
  6. Arun P Pandurangan
  7. Nasrin Jahan
  8. Mafalda Pires Damaso
  9. Dino Osmanović
  10. Cyril F Reboul
  11. Michelle A Dunstone
  12. Peter W Andrew
  13. Rana Lonnen
  14. Maya Topf
  15. Helen R Saibil
  16. Bart W Hoogenboom
(2014)
Stepwise visualization of membrane pore formation by suilysin, a bacterial cholesterol-dependent cytolysin
eLife 3:e04247.
https://doi.org/10.7554/eLife.04247

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https://doi.org/10.7554/eLife.04247

Further reading

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