Large-scale orientational order in bacterial colonies during inward growth

  1. Mustafa Basaran
  2. Y Ilker Yaman
  3. Tevfik Can Yüce
  4. Roman Vetter
  5. Askin Kocabas  Is a corresponding author
  1. Koç University, Turkey
  2. ETH Zurich, Switzerland

Abstract

During colony growth, complex interactions regulate the bacterial orientation, leading to the formation of large-scale ordered structures, including topological defects, microdomains, and branches. These structures may benefit bacterial strains, providing invasive advantages during colonization. Active matter dynamics of growing colonies drives the emergence of these ordered structures. However, additional biomechanical factors also play a significant role during this process. Here we show that the velocity profile of growing colonies creates strong radial orientation during inward growth when crowded populations invade a closed area. During this process, growth geometry sets virtual confinement and dictates the velocity profile. Herein, flow-induced alignment and torque balance on the rod-shaped bacteria result in a new stable orientational equilibrium in the radial direction. Our analysis revealed that the dynamics of these radially oriented structures also known as aster defects, depend on bacterial length and can promote the survival of the longest bacteria around localized nutritional hot spots. The present results indicate a new mechanism underlying structural order and provide mechanistic insights into the dynamics of bacterial growth on complex surfaces.

Data availability

The critical experimental data generated or analyzed during this study are provided as supporting video files.Code Availability:The codes utilized previously published open-source software from https://depts.washington.edu/soslab/gro/ and are made available on GitHub (https://github.com/mustafa-basaran/Large_Scale_Orientation_Bacteria).

Article and author information

Author details

  1. Mustafa Basaran

    Department of Physics, Koç University, Istanbul, Turkey
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1895-254X
  2. Y Ilker Yaman

    Department of Physics, Koç University, Istanbul, Turkey
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4094-616X
  3. Tevfik Can Yüce

    Department of Physics, Koç University, Istanbul, Turkey
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6888-2690
  4. Roman Vetter

    Department of Biosystems Science and Engineering, ETH Zurich, Basel, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2901-7036
  5. Askin Kocabas

    Department of Physics, Koç University, Istanbul, Turkey
    For correspondence
    akocabas@ku.edu.tr
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6930-1202

Funding

EMBO Installation Grant (IG 3275)

  • Askin Kocabas

BAGEP (young investigator award)

  • Askin Kocabas

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

Reviewing Editor

  1. Pierre Sens, Institut Curie, CNRS UMR168, France

Publication history

  1. Received: July 14, 2021
  2. Accepted: February 24, 2022
  3. Accepted Manuscript published: March 7, 2022 (version 1)
  4. Version of Record published: March 29, 2022 (version 2)

Copyright

© 2022, Basaran 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. Mustafa Basaran
  2. Y Ilker Yaman
  3. Tevfik Can Yüce
  4. Roman Vetter
  5. Askin Kocabas
(2022)
Large-scale orientational order in bacterial colonies during inward growth
eLife 11:e72187.
https://doi.org/10.7554/eLife.72187

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