[RETROSPECTIVE ANALYSIS OF BIOLOGICAL AND MOLECULAR-GENETIC PROPERTIES OF STRAINS - CAUSATIVE AGENTS OF CHOLERA - ISOLATED IN UKRAINE IN 1994 - 2011].

Aim: Retrospective analysis of biological and molecular-genetic properties of strains - cau- sative agents of cholera - isolated in the period of epidemics in Ukraine in 1994 - 2011.
Materials and Methods: Phenotypic and molecular-genetic properties of 5 strains of cholera vibrios, biovar El Tor isolated from cholera patients and 4 strains from the environmental samples were studied using traditional bacteriological and genetic methods. Detection of DNA for toxigenicity genes and genes characteristic for El Tor and classic biovar were carried out by PCR method using rea- gent kits <<AmpliSens- Vibrio cholerae FRT>> and <<Vibrio cholerae ctxB-rstR-rstC genes, REF>> an experimental test system). Sequencing of genomes of 4 strains of causative agents of cholera was carried out in genetic analyzer Ion Torrent Personal Genome Machine.
Results: Strains of cholera vibrios identified in Ukraine in 1994 and 2011 such as a typical toxigenic biovar El Tor (V cholerae Ο1, El Tor, Ogawa, Hly-, ctxA+, tcpA+) contain genes ofthe classic cholera vibrio in their genome and are genetically altered (hybrid) variants of cholera vibrio biovar El Tor producing enterotoxin CTI and having increased virulence, that was clinically manifested in predominance of severe forms of cholera in Mariupol of Donetsk region in 2011. Genome sequences ofthe 4 studied strains were deposited into the international database DDBJ/EMBL/GenBank.
Conclusion: The studied isolates were established to belong to a clade of strains associated with cholera outbreaks in Haiti and Asian continent, from where genetically altered strains of cholera vibrios biovar El Tor were introduced to Haiti in 2010, based on results of comparison of genomic sequences of the studied strains with genomes of V cholera strains from the international database GenBank.