Two different cell-cycle processes determine the timing of cell division in Escherichia coli
Abstract
Cells must control the cell cycle to ensure that key processes are brought to completion. In Escherichia coli, it is controversial whether cell division is tied to chromosome replication or to a replication-independent inter-division process. A recent model suggests instead that both processes may limit cell division with comparable odds in single cells. Here, we tested this possibility experimentally by monitoring single-cell division and replication over multiple generations at slow growth. We then perturbed cell width, causing an increase of the time between replication termination and division. As a consequence, replication became decreasingly limiting for cell division, while correlations between birth and division and between subsequent replication-initiation events were maintained. Our experiments support the hypothesis that both chromosome replication and a replication-independent inter-division process can limit cell division: the two processes have balanced contributions in non-perturbed cells, while our width perturbations increase the odds of the replication-independent process being limiting.
Data availability
All data generated or analysed during this study are included in supplemental datasets provided for each figure. Average quantities and sample sizes for each biological replicate can be found in Supplementary file 1. Supplementary file 2 contains all single-cell data used in this study.
Article and author information
Author details
Funding
H2020 European Research Council (679980)
- Sven van Teeffelen
Agence Nationale de la Recherche (ANR-10-LABX-62-IBEID)
- Sven van Teeffelen
Mairie de Paris Emergence program
- Sven van Teeffelen
Volkswagen Foundation Life program
- Sven van Teeffelen
Italian Association for Cancer Research AIRC-IG (23258)
- Marco Cosentino Lagomarsino
National Science Foundationce Foundation (310030_188642)
- Gabriele Micali
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Colin 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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