title: Role of a short tandem leucine/arginine repeat in strong mutator phenotype acquisition in a clinical isolate of Salmonella Typhimurium.
abstract: In this prospective study, a strong mutator strain of Salmonella Typhimurium was isolated from a collection of 130 human clinical strains of Salmonella. Sequence analysis of the mutS, mutL, and mutH genes, which encode three proteins that are essential for initiation of methyl-directed DNA mismatch repair, revealed insertion of a short tandem repeat (STR) of leucine/alanine in the histidine kinase-like ATPase domain of MutL. The role of this STR in the acquisition of the strong mutator phenotype was confirmed by the construction of an isogenic mutant (6bpinsmutL) from a normomutator strain of Salmonella Heidelberg. This result adds to the sparse body of knowledge about strong mutators and highlights the role of this STR as a hotspot for the acquisition of a strong mutator phenotype in Salmonella.
authors.affiliation: Equipe Microbiologie, EA 1254, SFR BIOSIT, Université Européenne de Bretagne, Rennes, France.
authors.forename: Hervé
authors.initials: H
authors.lastname: Le Bars
authors.forename: Latifa
authors.initials: L
authors.lastname: Bousarghin
authors.forename: Martine
authors.initials: M
authors.lastname: Bonnaure-Mallet
authors.forename: Anne
authors.initials: A
authors.lastname: Jolivet-Gougeon
mesh_terms: D000251:Adenosine Triphosphatases / Q000235:genetics*; D001120:Arginine / Q000235:genetics*; D001426:Bacterial Proteins / Q000235:genetics; D004260:DNA Repair; D006801:Humans; D007930:Leucine / Q000235:genetics*; D018895:Microsatellite Repeats / Q000235:genetics*; D009154:Mutation / Q000235:genetics*; D010641:Phenotype; D012480:Salmonella Infections / Q000382:microbiology; D012486:Salmonella typhimurium / Q000235:genetics* / Q000302:isolation & purification
chemical_list: D001426:Bacterial Proteins; D001120:Arginine; D000251:Adenosine Triphosphatases; D007930:Leucine