Fuse or die: how to survive the loss of Dam in Vibrio cholerae - Inserm - Institut national de la santé et de la recherche médicale Access content directly
Journal Articles Molecular Microbiology Year : 2014

Fuse or die: how to survive the loss of Dam in Vibrio cholerae


Dam methylates GATC sequences in γ-proteobacteria genomes, regulating several cellular functions including replication. In Vibrio cholerae, which has two chromosomes , Dam is essential for viability, owing to its role in chr2 replication initiation. In this study, we isolated spontaneous mutants of V. cholerae that were able to survive the deletion of dam. In these mutants, homologous recombination and chromosome dimer resolution are essential, unless DNA mismatch repair is inactivated. Furthermore, the initiator of chr2 repli-cation, RctB, is no longer required. We show that, instead, replication of chr2 is insured by spontaneous fusion with chr1 and piggybacking its replication machinery. We report that natural fusion of chr1 and chr2 occurred by two distinct recombination pathways: homologous recombination between repeated IS elements and site-specific recombination between dif sites. Lastly, we observed a preferential fusion of the two chromosomes in their terminus of replication.
Embargoed file
Embargoed file
Ne sera jamais visible

Dates and versions

inserm-01285641 , version 1 (09-03-2016)



Marie-Eve Val, Sean Patrick Kennedy, Alfonso Soler-Bistué, Valérie Barbe, Christiane Bouchier, et al.. Fuse or die: how to survive the loss of Dam in Vibrio cholerae. Molecular Microbiology, 2014, 91 (4), pp.665 - 678. ⟨10.1111/mmi.12483⟩. ⟨inserm-01285641⟩
216 View
1 Download



Gmail Facebook X LinkedIn More