Abstract

Bacterial biofilms can generate micro-heterogeneity in terms of surface structures. However, little is known about the associated changes in the physics of cell-cell interaction and its impact on the architecture of biofilms. Here, we used the type IV pilus of Neisseria gonorrhoeae to test whether variation of surface structures induces cell-sorting. We show that the rupture forces between pili are fine-tuned by post-translational modification. Bacterial sorting was dependent on pilus post-translational modification and pilus density. Active force generation was necessary for defined morphologies of mixed microcolonies. The observed morphotypes were in remarkable agreement with the differential strength of adhesion hypothesis proposing that a tug-of-war among surface structures of different cells governs cell sorting. We conclude that in early biofilms the density and rupture force of bacterial surface structures can trigger cell sorting based on similar physical principles as in developing embryos.

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Author details

  1. Enno R Oldewurtel

    Department of Physics, University of Cologne, Cologne, Germany
    Competing interests
    The authors declare that no competing interests exist.
  2. Nadzeya Kouzel

    Department of Physics, University of Cologne, Cologne, Germany
    Competing interests
    The authors declare that no competing interests exist.
  3. Lena Dewenter

    Department of Physics, University of Cologne, Cologne, Germany
    Competing interests
    The authors declare that no competing interests exist.
  4. Katja Henseler

    Department of Physics, University of Cologne, Cologne, Germany
    Competing interests
    The authors declare that no competing interests exist.
  5. Berenike Maier

    Department of Physics, University of Cologne, Cologne, Germany
    For correspondence
    berenike.maier@uni-koeln.de
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Roberto Kolter, Harvard Medical School, United States

Version history

  1. Received: August 12, 2015
  2. Accepted: September 23, 2015
  3. Accepted Manuscript published: September 24, 2015 (version 1)
  4. Version of Record published: October 29, 2015 (version 2)

Copyright

© 2015, Oldewurtel 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. Enno R Oldewurtel
  2. Nadzeya Kouzel
  3. Lena Dewenter
  4. Katja Henseler
  5. Berenike Maier
(2015)
Differential interaction forces govern bacterial sorting in early biofilms
eLife 4:e10811.
https://doi.org/10.7554/eLife.10811

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https://doi.org/10.7554/eLife.10811

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