title: Multiple-locus variable-number tandem repeat analysis of Vibrio cholerae in comparison with pulsed field gel electrophoresis and virulotyping.
abstract: Molecular analysis of Malaysian Vibrio cholerae was carried out using a multiple-locus variable-number tandem repeat analysis (MLVA) assay based on 7 loci of V. cholerae. The discriminatory ability of the assay was compared with pulsed-field gel electrophoresis (PFGE) using 43 Malaysian V. cholerae isolated from various sources. In addition, the virulotypes of the strains were determined. Based on MLVA, 38 allelic profiles were obtained (F = 0.63) while PFGE generated 35 pulsotypes (F = 0.71). Simpson's index of diversity for different VNTR loci ranged from 0.59 to 0.92. The combined loci increased the discriminatory index to 0.99 which was comparable with PFGE (D = 0.99). Most of the environmental non-O1/non-O139 strains harbored rtxA, rstR, toxR, and hlyA only, and the virulotype of this serogroup was significantly different (P < .01) from clinical/environmental O1 and environmental O139 strains. In conclusion, the MLVA assay developed in this study was a useful genotyping tool with comparable discriminatory power with PFGE. In addition, the combination of the two approaches can further distinguish the strains from different sources and geographical regions of isolation.
authors.affiliation: Faculty of Science, Institute of Biological Sciences, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Cindy Shuan Ju
authors.initials: CS
authors.lastname: Teh
authors.forename: Kek Heng
authors.initials: KH
authors.lastname: Chua
authors.forename: Kwai Lin
authors.initials: KL
authors.lastname: Thong
mesh_terms: D015373:Bacterial Typing Techniques / Q000379:methods*; D016521:Electrophoresis, Gel, Pulsed-Field / Q000379:methods*; D056426:Genetic Loci / Q000235:genetics*; D005838:Genotype; D018598:Minisatellite Repeats / Q000235:genetics*; D010802:Phylogeny; D014734:Vibrio cholerae / Q000145:classification* / Q000235:genetics / Q000472:pathogenicity*; D014774:Virulence / Q000235:genetics