Speed variations of bacterial replisomes
- Okinawa Institute of Science and Technology, Japan
Abstract
Replisomes are multi-protein complexes that replicate genomes with remarkable speed and accuracy. Despite their importance, their dynamics is poorly characterized, especially in vivo. In this paper, we present an approach to infer the replisome dynamics from the DNA abundance distribution measured in a growing bacterial population. Our method is sensitive enough to detect subtle variations of the replisome speed along the genome. As an application, we experimentally measured the DNA abundance distribution in Escherichia coli populations growing at different temperatures using deep sequencing. We find that the average replisome speed increases nearly five-fold between 17°C and 37°C. Further, we observe wave-like variations of the replisome speed along the genome. These variations correlate with previously observed variations of the mutation rate, suggesting a common dynamical origin. Our approach has the potential to elucidate replication dynamics in E. coli mutants and in other bacterial species.
Data availability
Sequence reads were deposited in the NCBI Sequence Read Archive with links to BioProject accession number PRJNA772106. Corresponding read frequencies along the genome were deposited in Zenodo (DOI:10.5281/zenodo.5577986).
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Escherichia coli DNA replication study: processed alignment datadoi: 10.5281/zenodo.5577986.
Article and author information
Author details
Funding
Japan Society for the Promotion of Science (JP18K03473)
- Simone Pigolotti
Deutsche Forschungsgemeinschaft (Projektnummer 452628014,Geschätszeichen: HA9374/1-1)
- Samuel Hauf
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2022, Bhat 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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Speed variations of bacterial replisomes
eLife 11:e75884.
https://doi.org/10.7554/eLife.75884
Further reading
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- Microbiology and Infectious Disease
- Physics of Living Systems
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