title: A toxin antitoxin system promotes the maintenance of the IncA/C-mobilizable Salmonella Genomic Island 1.
abstract: The multidrug resistance Salmonella Genomic Island 1 (SGI1) is an integrative mobilizable element identified in several enterobacterial pathogens. This chromosomal island requires a conjugative IncA/C plasmid to be excised as a circular extrachromosomal form and conjugally mobilized in trans. Preliminary observations suggest stable maintenance of SGI1 in the host chromosome but paradoxically also incompatibility between SGI1 and IncA/C plasmids. Here, using a Salmonella enterica serovar Agona clonal bacterial population as model, we demonstrate that a Toxin-Antitoxin (TA) system encoded by SGI1 plays a critical role in its stable host maintenance when an IncA/C plasmid is concomitantly present. This system, designated sgiAT for Salmonella genomic island 1 Antitoxin and Toxin respectively, thus seems to play a stabilizing role in a situation where SGI1 is susceptible to be lost through plasmid IncA/C-mediated excision. Moreover and for the first time, the incompatibility between SGI1 and IncA/C plasmids was experimentally confirmed.
authors: INRA, UMR1282, Infectiologie et Santé Publique, F-37380 Nouzilly, France.|Université François Rabelais de Tours, UMR1282 Infectiologie et Santé Publique, F-37000 Tours, France.
authors: Kevin T
authors: KT
authors: Huguet
authors: INRA, UMR1282, Infectiologie et Santé Publique, F-37380 Nouzilly, France.|Université François Rabelais de Tours, UMR1282 Infectiologie et Santé Publique, F-37000 Tours, France.
authors: Mathieu
authors: M
authors: Gonnet
authors: INRA, UMR1282, Infectiologie et Santé Publique, F-37380 Nouzilly, France.|Université François Rabelais de Tours, UMR1282 Infectiologie et Santé Publique, F-37000 Tours, France.
authors: Benoît
authors: B
authors: Doublet
authors: INRA, UMR1282, Infectiologie et Santé Publique, F-37380 Nouzilly, France.|Université François Rabelais de Tours, UMR1282 Infectiologie et Santé Publique, F-37000 Tours, France.
authors: Axel
authors: A
authors: Cloeckaert
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics; D002876:Chromosomes, Bacterial / Q000235:genetics; D016680:Genome, Bacterial; D042822:Genomic Instability; D044404:Genomic Islands; D016366:Open Reading Frames; D010750:Phosphoproteins / Q000235:genetics; D010957:Plasmids / Q000235:genetics; D019779:Salmonella enterica / Q000235:genetics*; D000075704:Toxin-Antitoxin Systems / Q000235:genetics*
chemical_list: D001426:Bacterial Proteins; C094163:IncA protein, bacteria; D010750:Phosphoproteins