A5042276865- Bacterial Genetics and Biotechnology
- Antibiotic Resistance in Bacteria
- Vibrio bacteria research studies
- Bacteriophages and microbial interactions
- Escherichia coli research studies
- RNA and protein synthesis mechanisms
- Legume Nitrogen Fixing Symbiosis
- Genomics and Phylogenetic Studies
- Plant Pathogenic Bacteria Studies
- Chromosomal and Genetic Variations
- Genetics, Bioinformatics, and Biomedical Research
- Cassava research and cyanide
- Protist diversity and phylogeny
- Enterobacteriaceae and Cronobacter Research
- DNA and Biological Computing
- DNA Repair Mechanisms
Institut Pasteur
2018-2024
Centre National de la Recherche Scientifique
2016-2024
Université de Toulouse
2014-2024
Université Toulouse III - Paul Sabatier
2014-2024
Laboratoire de Microbiologie et Génétique Moléculaires
2014-2024
University of Lausanne
2023-2024
Université Paris Cité
2021-2024
Centre de Gestion Scientifique
2018-2021
Integrons are adaptive bacterial devices that rearrange promoter-less gene cassettes into variable ordered arrays under stress conditions, thereby sampling combinatorial phenotypic diversity. Chromosomal integrons often carry hundreds of silent cassettes, with integrase-mediated recombination leading to rampant DNA excision and integration, posing a potential threat genome integrity. How this activity is regulated controlled, particularly through selective pressures, maintain such large...
Abstract The replication of the two chromosomes in pathogenic bacterium Vibrio cholerae is coordinated by binding initiator protein RctB to a checkpoint sequence, crtS . Replication on primary chromosome (Chr1) triggers secondary (Chr2), but details are poorly understood. Here, we analyze patterns V. genome across various cell cycle stages. We find that primarily binds sites inhibiting initiation at Chr2 origin ( ori2 ). This inhibitory effect counteracted when replicated Chr1, causing shift...
Bacteria rely on an arsenal of weapons to challenge their opponents in highly competitive environments. To specifically counter closely related bacteria, specialized with a narrow activity spectrum are deployed, particularly contractile phage tail-like particles or R-tailocins. Their production leads the lysis producing cells, indicating that expression must be carefully orchestrated so only small percentage cells produce R-tailocins for benefit entire population. In this study, we set out...
Significance This study focuses on a molecular machine (Xer/ dif /FtsK) involved in circular chromosome processing during the bacterial cell cycle. Xer site-specific recombinases are well known to act at chromosomal (dimer resolution) sites for dimer resolution (CDR). The Xer/ recombination is, however, highly versatile and is also implicated integration excision of mobile genetic elements (MGE). Whereas CDR depends FtsK DNA translocase, MGE mobility somehow escapes this control. Focusing...
Integrons confer a rapid adaptation capability to bacteria. Integron integrases are able capture and shuffle novel functions embedded in cassettes. Here, we investigated cassette recruitment the Vibrio cholerae chromosomal integron during horizontal transfer. We demonstrated that endogenous integrase expression is sufficiently triggered, after SOS response induction mediated by entry of cassettes conjugation natural transformation, mediate significant insertions. These insertions...
Bacteria contain a primary chromosome and, frequently, either essential secondary chromosomes or dispensable megaplasmids of plasmid origin. Incoming plasmids are often poorly adapted to their hosts and stabilization requires integration with the host's cellular mechanisms in process termed domestication. All Vibrio, including pathogenic species, carry domesticated (Chr2) where replication is coordinated that (Chr1). Chr2 triggered by an intergenic sequence (crtS) located on Chr1. Yet,...
Abstract Bacterial genomes contain a plethora of secondary replicons divergent size. Circular must carry system for resolving dimeric forms, resulting from recombination between sister copies. These systems use site-specific recombinases. Among these, the XerCD recombinase resolves dimers chromosomes and certain plasmids using different controls. We have analyzed dimer resolution functions in enterobacterial show that, addition to main chromosomes, is preferentially used by small largest...
Abstract The cell cycle-regulated DNA methyltransferase CcrM is conserved in most Alphaproteobacteria, but its role bacteria with complex or multicentric genomes remains unexplored. Here, we compare the methylome, transcriptome and phenotypes of wild-type CcrM-depleted Agrobacterium tumefaciens cells a dicentric chromosome two essential replication origins. We find that methylation has pleiotropic impact on motility, biofilm formation viability. Remarkably, promotes expression repABCCh2...
Vibrio cholerae, the pathogenic bacterium that causes cholera, has two chromosomes (Chr1, Chr2) replicate in a well-orchestrated sequence. Chr2 initiation is triggered only after replication of crtS site on Chr1. The initiator replication, RctB, displays activities corresponding with its different binding sites: at iteron sites, repressor 39m and trigger site. mechanism by which RctB relays signal to initiate from not well-understood. In this study, we provide new insights into how regulated...
Abstract Over 10% of bacteria have expanded their genomes through the domestication megaplasmids, which subsequently evolved into secondary chromosomes encoding core functions. A fundamental challenge this genomic expansion is coordinating replication multiple replicons within a single cell cycle. In Vibrio cholerae , chromosome (Chr2) intricately linked to primary (Chr1) via unique checkpoint sequence, crtS . This sequence binds initiator Chr2, RctB. While on Chr1 triggers Chr2 replication,...
Bacterial genomes contain a plethora of secondary replicons divergent size. Circular must carry system for resolving dimeric forms, resulting from recombination between sister copies. These systems use site-specific recombinases. Among these, the XerCD recombinase resolves dimers chromosomes and certain plasmids, using different modes regulation. We have analyzed dimer resolution functions in enterobacterial show that, addition to main chromosomes, is preferentially used by small plasmids...
Abstract Integrons are adaptive bacterial devices that rearrange promoter less gene cassettes into variable ordered arrays under stress conditions, to sample combinatorial phenotypic diversity. Chromosomal integrons often carry hundreds of silent cassettes, with integrase-mediated recombination leading rampant DNA excision and integration, posing a potential threat genome integrity. How this activity is regulated controlled, particularly through selective pressures, maintain such large...
ABSTRACT The c ell ycle-regulated DNA m ethyltransferase CcrM is conserved in most Alphaproteobacteria , but its role bacteria with complex or multicentric genomes remains unexplored. Here, we compare the methylome, transcriptome and phenotypes of wild-type CcrM-depleted Agrobacterium tumefaciens cells a dicentric genome two essential replication origins. We find that methylation has pleiotropic impact on motility, biofilm formation viability. Remarkably, promotes expression repABC Ch2...
Abstract Integrons are genetic systems conferring to bacteria a rapid adaptation capability. The integron integrase is able capture, stockpile and shuffle novel functions embedded in cassettes. This involves the recognition of both substrates, attI site, cassette associated attC sites. can be sedentary chromosomally located (SCI) or, carried by conjugative plasmids (Mobile Integron, MI), hence favoring their dissemination among bacteria. Here, for first time, we investigate recruitment...