1. Structural Biology and Molecular Biophysics
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Structure of a type IV pilus machinery in the open and closed state

  1. Vicki A M Gold  Is a corresponding author
  2. Ralf Salzer
  3. Beate Averhoff
  4. Werner Kühlbrandt
  1. Max Planck Institute of Biophysics, Germany
  2. Goethe University Frankfurt, Germany
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Cite this article as: eLife 2015;4:e07380 doi: 10.7554/eLife.07380

Abstract

Proteins of the secretin family form large macromolecular complexes, which assemble in the outer membrane of Gram-negative bacteria. Secretins are major components of type II and III secretion systems and are linked to extrusion of type IV pili (T4P) and to DNA uptake. By electron cryo-tomography of whole T. thermophilus cells, we determined the in situ structure of a T4P molecular machine in the open and the closed state. Comparison reveals a major conformational change whereby the N-terminal domains of the central secretin PilQ shift by ~30 Å, and two periplasmic gates open to make way for pilus extrusion. Furthermore, we determine the structure of the assembled pilus.

Article and author information

Author details

  1. Vicki A M Gold

    Department of Structural Biology, Max Planck Institute of Biophysics, Frankfurt am Main, Germany
    For correspondence
    vicki.gold@biophys.mpg.de
    Competing interests
    No competing interests declared.
  2. Ralf Salzer

    Molecular Microbiology and Bioenergetics, Institute of Molecular Biosciences, Goethe University Frankfurt, Frankfurt am Main, Germany
    Competing interests
    No competing interests declared.
  3. Beate Averhoff

    Molecular Microbiology and Bioenergetics, Institute of Molecular Biosciences, Goethe University Frankfurt, Frankfurt am Main, Germany
    Competing interests
    No competing interests declared.
  4. Werner Kühlbrandt

    Department of Structural Biology, Max Planck Institute of Biophysics, Frankfurt am Main, Germany
    Competing interests
    Werner Kühlbrandt, Reviewing editor, eLife.

Reviewing Editor

  1. Stephen C Harrison, Harvard Medical School, Howard Hughes Medical Institute, United States

Publication history

  1. Received: March 9, 2015
  2. Accepted: May 20, 2015
  3. Accepted Manuscript published: May 21, 2015 (version 1)
  4. Version of Record published: June 12, 2015 (version 2)

Copyright

© 2015, Gold 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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