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bioRxiv · 10.1101/2023.05.26.541695

DNA replication is not a limiting factor for the rapid growth of Vibrio natriegens

Ramming, L.·Stukenberg, D.·Sanchez Olmos, M. d. C.·Becker, A.·Schindler, D.
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Abstract

DNA replication prior to cell division is essential for the proliferation of all cells. Bacterial chromosomes are replicated bidirectionally from a single origin of replication, with replication proceeding at about 1000 bp per second. For the best-studied model organism, Escherichia coli, this translates into a replication time of about 40 min for its 4.6 Mb chromosome. Nevertheless, E. coli can propagate by overlapping replication cycles with a maximum short doubling time of 20 min. The fastest growing bacterium known today, Vibrio natriegens, is able to replicate with a generation time of less than 10 min. It has a bipartite genome with chromosome sizes of 3.2 and 1.9 Mb. Is simultaneous replication from two origins a prerequisite for its rapid growth? We fused the two chromosomes of V. natriegens to create a strain carrying a 5.2 Mb chromosome with a single origin of replication. Compared to the wild-type, this strain showed little deviation in growth rate. This suggests that the split genome is not a prerequisite for rapid growth, and that DNA replication is not an important growth rate-limiting factor.

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Ramming, L., Stukenberg, D., Sanchez Olmos, M. d. C., Becker, A., Schindler, D.. 2023-05-26. DNA replication is not a limiting factor for the rapid growth of Vibrio natriegens. https://doi.org/10.1101/2023.05.26.541695

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