DEVELOPMENT OF A MULTIPLEX PCR FOR SIMULTANEOUS IDENTIFICATION OF GENETICALLY ALTERED TOXIGENIC Vibrio cholerae STRAINS AND THEIR DIFFERENTIATION BY EPIDEMIC POTENTIAL

Abstract

A method for detecting toxigenic genetically altered strains of Vibrio cholerae O1 serogroup eltor biotype and their differentiation into strains with high and low epidemic potential has been developed. To this purpose, the structure of the Vibrio Pan-demic Island-II (VSP-II) was determined by multiplex PCR in two reaction mixtures. The toxigenic strains of V. cholerae O1 genovariants eltor biotype with intact VSP-II and low epidemic po-tential are characterized by gene amplicons rfbO1, rstC, ctxA, ctxBClass, vc0502, and vc0514. The toxigenic V. cholerae O1 genovariants eltor biotype with high epidemic potential and long de-letion in VSP-II have amplified gene fragments rfbO1, rstC, ctxA, ctxBClass, and vc0514. The high specificity of this method was confirmed by testing of closely related species of Vibrio genus and Enterobacteriaceae. The developed multiplex PCR was used in the investigation of 52 collectible V. cholerae strains, 8 of which were found to be toxigenic genetically altered strains of V. cholerae O1 serogroup biotype with high epidemic potential that were imported to the Russian Federation in 2004—2012. The de-signed multiplex PCR can be used in the epidemiological investi-gations and complete characterization of V. cholerae imported strains and certification of Vibrio cholerae strains, which are de-posited in the State Collection of Pathogenic Bacteria of the Rus-sian Research Anti-Plague Institute Microbe.