title: Multilocus sequence typing system for Campylobacter jejuni.
abstract: The gram-negative bacterium Campylobacter jejuni has extensive reservoirs in livestock and the environment and is a frequent cause of gastroenteritis in humans. To date, the lack of (i) methods suitable for population genetic analysis and (ii) a universally accepted nomenclature has hindered studies of the epidemiology and population biology of this organism. Here, a multilocus sequence typing (MLST) system for this organism is described, which exploits the genetic variation present in seven housekeeping loci to determine the genetic relationships among isolates. The MLST system was established using 194 C. jejuni isolates of diverse origins, from humans, animals, and the environment. The allelic profiles, or sequence types (STs), of these isolates were deposited on the Internet (http://mlst.zoo.ox.ac.uk), forming a virtual isolate collection which could be continually expanded. These data indicated that C. jejuni is genetically diverse, with a weakly clonal population structure, and that intra- and interspecies horizontal genetic exchange was common. Of the 155 STs observed, 51 (26% of the isolate collection) were unique, with the remainder of the collection being categorized into 11 lineages or clonal complexes of related STs with between 2 and 56 members. In some cases membership in a given lineage or ST correlated with the possession of a particular Penner HS serotype. Application of this approach to further isolate collections will enable an integrated global picture of C. jejuni epidemiology to be established and will permit more detailed studies of the population genetics of this organism.
authors.affiliation: Wellcome Trust Centre for the Epidemiology of Infectious Disease, Department of Zoology, University of Oxford, Oxford OX1 3FY, United Kingdom.
authors.forename: K E
authors.initials: KE
authors.lastname: Dingle
authors.forename: F M
authors.initials: FM
authors.lastname: Colles
authors.forename: D R
authors.initials: DR
authors.lastname: Wareing
authors.forename: R
authors.initials: R
authors.lastname: Ure
authors.forename: A J
authors.initials: AJ
authors.lastname: Fox
authors.forename: F E
authors.initials: FE
authors.lastname: Bolton
authors.forename: H J
authors.initials: HJ
authors.lastname: Bootsma
authors.forename: R J
authors.initials: RJ
authors.lastname: Willems
authors.forename: R
authors.initials: R
authors.lastname: Urwin
authors.forename: M C
authors.initials: MC
authors.lastname: Maiden
mesh_terms: D000483:Alleles; D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics; D015373:Bacterial Typing Techniques; D002169:Campylobacter Infections / Q000382:microbiology* / Q000662:veterinary; D016123:Campylobacter jejuni / Q000145:classification* / Q000235:genetics*; D002874:Chromosome Mapping; D004269:DNA, Bacterial / Q000235:genetics; D004783:Environmental Microbiology; D005798:Genes, Bacterial; D014644:Genetic Variation; D006801:Humans; D010802:Phylogeny; D017422:Sequence Analysis, DNA; D012703:Serotyping
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial