Surface-to-volume scaling and aspect ratio preservation in rod-shaped bacteria
- University College London, United Kingdom
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.
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Article and author information
Author details
Shiladitya Banerjee
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.
Copyright
© 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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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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