title: O-antigen diversity and lateral transfer of the wbe region among Vibrio splendidus isolates.
abstract: The O-antigen is a highly diverse structure expressed on the outer surface of Gram-negative bacteria. The products responsible for O-antigen synthesis are encoded in the wbe region, which exhibits extensive genetic diversity. While heterogeneous O-antigens are observed within Vibrio species, characterization of these structures has been devoted almost exclusively to pathogens. Here, we investigate O-antigen diversity among coastal marine Vibrio splendidus-like isolates. The wbe region was first identified and characterized using the sequenced genomes of strains LGP32, 12B01 and Med222. These regions were genetically diverse, reflective of their expressed O-antigen. Additional isolates from physically distinct habitats in Plum Island Estuary (MA, USA), including within animal hosts and on suspended particles, were further characterized based on multilocus sequence analysis (MLSA) and O-antigen profiles. Results showed serotype diversity within an ecological setting. Among 48 isolates which were identical in three MLSA genes, 41 showed gpm genetic diversity, a gene closely linked to the wbe locus, and at least 12 expressed different O-antigen profiles further suggesting wbe genetic diversity. Our results demonstrate O-antigen hyper-variability among these environmental strains and suggest that frequent lateral gene transfer generates wbe extensive diversity among V. splendidus and its close relatives.
authors.affiliation: Civil and Environmental Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA. hansw@mit.edu
authors.forename: Hans
authors.initials: H
authors.lastname: Wildschutte
authors.forename: Sarah P
authors.initials: SP
authors.lastname: Preheim
authors.forename: Yasiel
authors.initials: Y
authors.lastname: Hernandez
authors.forename: Martin F
authors.initials: MF
authors.lastname: Polz
mesh_terms: D000940:Antigenic Variation; D001483:Base Sequence; D022761:Gene Transfer, Horizontal; D056426:Genetic Loci; D014644:Genetic Variation; D016680:Genome, Bacterial; D008404:Massachusetts; D008969:Molecular Sequence Data; D058885:Multilocus Sequence Typing; D019081:O Antigens / Q000032:analysis / Q000145:classification / Q000235:genetics; D016366:Open Reading Frames; D010802:Phylogeny; D017422:Sequence Analysis, DNA; D012703:Serotyping; D014733:Vibrio / Q000235:genetics* / Q000276:immunology*; D014871:Water Microbiology
chemical_list: D019081:O Antigens