title: Retrospective Analysis of Serotype Switching of Vibrio cholerae O1 in a Cholera Endemic Region Shows It Is a Non-random Process.
abstract: Genomic data generated from clinical Vibrio cholerae O1 isolates collected over a five year period in an area of Kolkata, India with seasonal cholera outbreaks allowed a detailed genetic analysis of serotype switching that occurred from Ogawa to Inaba and back to Ogawa. The change from Ogawa to Inaba resulted from mutational disruption of the methyltransferase encoded by the wbeT gene. Re-emergence of the Ogawa serotype was found to result either from expansion of an already existing Ogawa clade or reversion of the mutation in an Inaba clade. Our data suggests that such transitions are not random events but rather driven by as yet unidentified selection mechanisms based on differences in the structure of the O1 antigen or in the serotype-determining wbeT gene.
authors.affiliation: Department of Microbiology and Immunology, Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden.
authors.forename: Stefan L
authors.initials: SL
authors.lastname: Karlsson
authors.affiliation: Wellcome Trust Sanger Institute, Cambridge, United Kingdom.|Department of Pathogen Molecular Biology, the London School of Hygiene and Tropical Medicine, London, United Kingdom.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Thomson
authors.affiliation: Wellcome Trust Sanger Institute, Cambridge, United Kingdom.
authors.forename: Ankur
authors.initials: A
authors.lastname: Mutreja
authors.affiliation: Cardiff University, Cardiff, United Kingdom.
authors.forename: Thomas
authors.initials: T
authors.lastname: Connor
authors.affiliation: Indian Council of Medical Research, New Delhi, India.
authors.forename: Dipika
authors.initials: D
authors.lastname: Sur
authors.affiliation: Johns Hopkins Bloomberg School of Public Health, Maryland, Baltimore, United States of America.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Ali
authors.affiliation: International Centre for Diarrhoeal Disease Research, Dhaka, Dhaka Bangladesh.
authors.forename: John
authors.initials: J
authors.lastname: Clemens
authors.affiliation: Wellcome Trust Sanger Institute, Cambridge, United Kingdom.
authors.forename: Gordon
authors.initials: G
authors.lastname: Dougan
authors.affiliation: Department of Microbiology and Immunology, Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden.
authors.forename: Jan
authors.initials: J
authors.lastname: Holmgren
authors.affiliation: Department of Microbiology and Immunology, Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden.
authors.forename: Michael
authors.initials: M
authors.lastname: Lebens
mesh_terms: D002771:Cholera / Q000453:epidemiology* / Q000382:microbiology*; D004196:Disease Outbreaks; D019353:Endemic Diseases; D016680:Genome, Bacterial; D006801:Humans; D007194:India / Q000453:epidemiology; D008780:Methyltransferases / Q000235:genetics; D009154:Mutation; D019081:O Antigens / Q000737:chemistry / Q000235:genetics; D010802:Phylogeny; D012189:Retrospective Studies; D017422:Sequence Analysis, DNA; D065288:Serogroup; D012703:Serotyping; D041241:Vibrio cholerae O1 / Q000145:classification / Q000235:genetics* / Q000276:immunology* / Q000302:isolation & purification
chemical_list: D019081:O Antigens; D008780:Methyltransferases