1. Physics of Living Systems
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Surface-to-volume scaling and aspect ratio preservation in rod-shaped bacteria

  1. Nikola Ojkic
  2. Diana Serbanescu
  3. Shiladitya Banerjee  Is a corresponding author
  1. University College London, United Kingdom
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Cite this article as: eLife 2019;8:e47033 doi: 10.7554/eLife.47033


Rod-shaped bacterial cells can readily adapt their lengths and widths in response to environmental changes. While many recent studies have focused on the mechanisms underlying bacterial cell size control, it remains largely unknown how the coupling between cell length and width results in robust control of rod-like bacterial shapes. In this study we uncover a conserved surface-to-volume scaling relation in Escherichia coli and other rod-shaped bacteria, resulting from the preservation of cell aspect ratio. To explain the mechanistic origin of aspect-ratio control, we propose a quantitative model for the coupling between bacterial cell elongation and the accumulation of an essential division protein, FtsZ. This model reveals a mechanism for why bacterial aspect ratio is independent of cell size and growth conditions, and predicts cell morphological changes in response to nutrient perturbations, antibiotics, MreB or FtsZ depletion, in quantitative agreement with experimental data.

Article and author information

Author details

  1. Nikola Ojkic

    Department of Physics and Astronomy, University College London, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  2. Diana Serbanescu

    Department of Physics and Astronomy, University College London, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  3. Shiladitya Banerjee

    Department of Physics and Astronomy, University College London, London, United Kingdom
    For correspondence
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8000-2556


Royal Society (URF/R1/180187)

  • Shiladitya Banerjee

Royal Society (RGF/EA/181044)

  • Shiladitya Banerjee

Engineering and Physical Sciences Research Council (EP/R029822/1)

  • Shiladitya Banerjee

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

Reviewing Editor

  1. Raymond E Goldstein, University of Cambridge, United Kingdom

Publication history

  1. Received: March 20, 2019
  2. Accepted: August 28, 2019
  3. Accepted Manuscript published: August 28, 2019 (version 1)
  4. Version of Record published: September 12, 2019 (version 2)


© 2019, Ojkic 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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