Single-cell growth inference of Corynebacterium glutamicum reveals asymptotically linear growth
Abstract
Regulation of growth and cell size is crucial for the optimization of bacterial cellular function. So far, single bacterial cells have been found to grow predominantly exponentially, which implies the need for tight regulation to maintain cell size homeostasis. Here, we characterize the growth behavior of the apically growing bacterium Corynebacterium glutamicum using a novel broadly applicable inference method for single-cell growth dynamics. Using this approach, we find that C. glutamicum exhibits asymptotically linear single-cell growth. To explain this growth mode, we model elongation as being rate-limited by the apical growth mechanism. Our model accurately reproduces the inferred cell growth dynamics and is validated with elongation measurements on a transglycosylase deficient ΔrodA mutant. Finally, with simulations we show that the distribution of cell lengths is narrower for linear than exponential growth, suggesting that this asymptotically linear growth mode can act as a substitute for tight division length and division symmetry regulation.
Data availability
All data generated during this study are included in the manuscript and supporting files.
Article and author information
Author details
Funding
Graduate School for Quantitative Biosciences Munich (Graduate Student Stipend)
- Joris Jan Boudewijn Messelink
Deutsche Forschungsgemeinschaft (TRR 174 project P06)
- Joris Jan Boudewijn Messelink
- Chase P Broedersz
Deutsche Forschungsgemeinschaft (TRR 174 project P05)
- Fabian Meyer
- Marc Bramkamp
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Messelink 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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