Surface-to-volume scaling and aspect ratio preservation in rod-shaped bacteria

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Abstract

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.

Data availability

All data generated or analysed during this study are referenced in the manuscript and supporting files.

The following previously published data sets were used

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Article and author information

Author details

Nikola Ojkic

Department of Physics and Astronomy, University College London, London, United Kingdom

Competing interests
The authors declare that no competing interests exist.
Diana Serbanescu

Department of Physics and Astronomy, University College London, London, United Kingdom

Competing interests
The authors declare that no competing interests exist.
Shiladitya Banerjee

Department of Physics and Astronomy, University College London, London, United Kingdom

For correspondence
shiladitya.banerjee@ucl.ac.uk

Competing interests
The authors declare that no competing interests exist.

"This ORCID iD identifies the author of this article:" 0000-0001-8000-2556

Funding

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.

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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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Nikola Ojkic
Diana Serbanescu
Shiladitya Banerjee

(2019)

Surface-to-volume scaling and aspect ratio preservation in rod-shaped bacteria

eLife 8:e47033.

https://doi.org/10.7554/eLife.47033

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