Serological and molecular characteristics of Vibrio vulnificus biotype 3: evidence for high clonality.
Vibrio vulnificus biotype 3 has been implicated as the causative pathogen of an ongoing disease outbreak that erupted in Israel in 1996. Recent work based on multi-locus sequence typing (MLST) showed that V. vulnificus biotype 3 is genetically homogeneous. The aim of this study was to investigate the existence of subpopulations within this homogeneous biotype by characterizing the surface antigens and analysing the sequence diversity of selected outer-membrane protein (OMP)-encoding genes. Rabbit antisera were prepared against biotype 1, 2 and 3 strains. The results of the slide-agglutination test, dot-blot assay (using fresh and boiled cells), and immunoblotting of lipopolysaccharides (LPS) and OMPs were evaluated. By slide-agglutination and dot-blot assays all biotype 3 strains agglutinated with the selected biotype 3 strain. This homogeneity was supported by immunoblot analysis of the LPS. Analysis of OMP patterns revealed that all three biotypes share a considerable number of common bands that are antigenically related. Cluster analysis of DNA sequence data from selected OMP-encoding genes showed that biotype 3 strains form a genetically distinct and homogeneous clone. The homogeneity of surface antigens and the lack of any sequence diversity among both housekeeping and OMP-encoding genes reaffirms the highly clonal nature of biotype 3 and suggests that it has only recently descended from the parent population of V. vulnificus.
Bisharat
Naiel
N
Department of Epidemiology and Preventive Medicine, School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Ramat Aviv, Israel.
Amaro
Carmen
C
Departamento de Microbiologia y Ecologia, Campus de Burjassot, Universidad de Valencia, Valencia 46100, Spain.
Fouz
Belén
B
Departamento de Microbiologia y Ecologia, Campus de Burjassot, Universidad de Valencia, Valencia 46100, Spain.
Llorens
Amparo
A
Departamento de Microbiologia y Ecologia, Campus de Burjassot, Universidad de Valencia, Valencia 46100, Spain.
Cohen
Daniel I
DI
Department of Epidemiology and Preventive Medicine, School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Ramat Aviv, Israel.
D000372:Agglutination Tests; D000942:Antigens, Bacterial / Q000276:immunology; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics; D001483:Base Sequence; D016000:Cluster Analysis; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D019143:Evolution, Molecular; D014644:Genetic Variation; D006801:Humans; D015151:Immunoblotting; D007557:Israel; D008070:Lipopolysaccharides / Q000276:immunology; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D017385:Sequence Homology; D014735:Vibrio Infections / Q000453:epidemiology / Q000382:microbiology*; D041261:Vibrio vulnificus / Q000145:classification* / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification
D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D004269:DNA, Bacterial; D008070:Lipopolysaccharides