CryoEM structures of membrane pore and prepore complex reveal cytolytic mechanism of Pneumolysin

  1. Katharina van Pee
  2. Alexander Neuhaus
  3. Edoardo D'Imprima
  4. Deryck J Mills
  5. Werner Kühlbrandt  Is a corresponding author
  6. Özkan Yildiz  Is a corresponding author
  1. Max Planck Institute of Biophysics, Germany

Abstract

Many pathogenic bacteria produce pore-forming toxins to attack and kill human cells. We have determined the 4.5 Å structure of the ~2.2 MDa pore complex of pneumolysin, the main virulence factor of Streptococcus pneumoniae, by cryoEM. The pneumolysin pore is a 400 Å ring of 42 membrane-inserted monomers. Domain D3 of the soluble toxin refolds into two ~85 Å β-hairpins that traverse the lipid bilayer and assemble into a 168-strand β-barrel. The pore complex is stabilized by salt bridges between β-hairpins of adjacent subunits and an internal α-barrel. The apolar outer barrel surface with large sidechains is immersed in the lipid bilayer, while the inner barrel surface is highly charged. Comparison of the cryoEM pore complex to the prepore structure obtained by electron cryo-tomography and the x-ray structure of the soluble form reveals the detailed mechanisms by which the toxin monomers insert into the lipid bilayer to perforate the target membrane.

Data availability

The following data sets were generated
    1. van Pee K
    2. Yildiz O
    (2016) Crystal structure of pneumolysin D168A mutant
    Publicly available at the RCSB Protein Data Bank (accession no: 5AOE).
The following previously published data sets were used
    1. van Pee K
    2. Yildiz O
    (2015) Crystal structure of wild type pneumolysin.
    Publicly available at the RCSB Protein Data Bank (accession no: 5AOD).

Article and author information

Author details

  1. Katharina van Pee

    Department of Structural Biology, Max Planck Institute of Biophysics, Frankfurt am Main, Germany
    Competing interests
    No competing interests declared.
  2. Alexander Neuhaus

    Department of Structural Biology, Max Planck Institute of Biophysics, Frankfurt am Main, Germany
    Competing interests
    No competing interests declared.
  3. Edoardo D'Imprima

    Department of Structural Biology, Max Planck Institute of Biophysics, Frankfurt am Main, Germany
    Competing interests
    No competing interests declared.
  4. Deryck J Mills

    Department of Structural Biology, Max Planck Institute of Biophysics, Frankfurt am Main, Germany
    Competing interests
    No competing interests declared.
  5. Werner Kühlbrandt

    Department of Structural Biology, Max Planck Institute of Biophysics, Frankfurt am Main, Germany
    For correspondence
    werner.kuehlbrandt@biophys.mpg.de
    Competing interests
    Werner Kühlbrandt, Reviewing editor, eLife.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2013-4810
  6. Özkan Yildiz

    Department of Structural Biology, Max Planck Institute of Biophysics, Frankfurt am Main, Germany
    For correspondence
    Oezkan.Yildiz@biophys.mpg.de
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3659-2805

Funding

Max-Planck-Gesellschaft (DepartmentSB)

  • Katharina van Pee
  • Alexander Neuhaus
  • Edoardo D'Imprima
  • Deryck J Mills
  • Werner Kühlbrandt
  • Özkan Yildiz

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Sjors HW Scheres, MRC Laboratory of Molecular Biology,, United Kingdom

Publication history

  1. Received: November 28, 2016
  2. Accepted: March 17, 2017
  3. Accepted Manuscript published: March 21, 2017 (version 1)
  4. Version of Record published: May 2, 2017 (version 2)

Copyright

© 2017, van Pee 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. Katharina van Pee
  2. Alexander Neuhaus
  3. Edoardo D'Imprima
  4. Deryck J Mills
  5. Werner Kühlbrandt
  6. Özkan Yildiz
(2017)
CryoEM structures of membrane pore and prepore complex reveal cytolytic mechanism of Pneumolysin
eLife 6:e23644.
https://doi.org/10.7554/eLife.23644

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