title: Inactivation of mismatch repair increases the diversity of Vibrio parahaemolyticus.
abstract: Inactivation of mismatch repair (MMR) has been shown to increase the accumulation of spontaneous mutations and frequency of recombination for diverse pathogenic bacteria. Currently, little is known regarding the role of mutator phenotypes for the diversification of natural populations of opportunistic human pathogens in marine environments. In this study, a higher frequency of mutators was detected among V. parahaemolyticus strains obtained from environmental sources compared with clinical sources. Inactivation of the MMR gene mutS caused increased antibiotic resistance and phase variation resulting in translucent colony morphologies. Increased nucleotide diversity in mutS and rpoB alleles from mutator compared with wild-type strains indicated a significant contribution of the mutator phenotype to the evolution of select genes. The results of this study indicate that the inactivation of MMR in V. parahaemolyticus leads to increased genetic and phenotypic diversity. This study is the first to report a higher frequency of natural mutators among Vibrio environmental strains and to provide evidence that inactivation of MMR increases the diversity of V. parahaemolyticus.
authors.affiliation: School of Biology, Georgia Institute of Technology, Atlanta, GA 30332, USA.
authors.forename: Tracy H
authors.initials: TH
authors.lastname: Hazen
authors.forename: K Danielle
authors.initials: KD
authors.lastname: Kennedy
authors.forename: Shen
authors.initials: S
authors.lastname: Chen
authors.forename: Soojin V
authors.initials: SV
authors.lastname: Yi
authors.forename: Patricia A
authors.initials: PA
authors.lastname: Sobecky
mesh_terms: D053843:DNA Mismatch Repair; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004783:Environmental Microbiology; D055786:Gene Knockout Techniques; D014644:Genetic Variation; D006801:Humans; D008969:Molecular Sequence Data; D051719:MutS DNA Mismatch-Binding Protein / Q000235:genetics; D017422:Sequence Analysis, DNA; D014735:Vibrio Infections / Q000382:microbiology*; D014736:Vibrio parahaemolyticus / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*
chemical_list: D004269:DNA, Bacterial; D051719:MutS DNA Mismatch-Binding Protein