Multiple-Locus Variable-Number Tandem Repeat Analysis ofVibrio choleraein Comparison with Pulsed Field Gel Electrophoresis and Virulotyping

[摘要] Molecular analysis of MalaysianVibrio choleraewas carried out using a multiple-locus variable-number tandem repeat analysis (MLVA) assay based on 7 loci ofV. cholerae. The discriminatory ability of the assay was compared with pulsed-field gel electrophoresis (PFGE) using 43 MalaysianV. choleraeisolated 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 harboredrtxA,rstR,toxR, andhlyA 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.

[学科分类] 基础医学