Phenotypic and Genetic Analysis of Altered Variants of Vibrio cholerae Biovar El Tor

S. P. Zadnova, A. V. Shashkova, Ya. M. Krasnov, N. I. Smirnova
2012 Problems of Particularly Dangerous Infections  
Ключевые слова: измененные варианты V. cholerae биовара эльтор, продукция холерного токсина, копийность генов ctxAB, секвенирование промоторной области. Determined is cholera toxin production by altered Vibrio cholerae O1 eltor strains, isolated on the territory of Russia in 1993-2010, which contain classical type ctxB gene. Studied are their genetic characteristics related to the production of this virulence factor. Determined is that altered eltor variants yield 10 to 20 times more cholera
more » ... in than typical eltor strains. Changes in promotor region of ctxAB operon are not detected but elucidated is that 90 % of studied altered strains contain two copies of CTXϕ prophage in their genome whereas typical strains carry one copy of CTXϕ prophage. Despite the higher copy number of CTXϕ prophage, the identified differences in production of cholera toxin can be associated mostly with a change of transcriptional activity of regulatory genes. That causes the active production of cholera toxin by the altered variants of Vibrio cholerae eltor in non typical environment. Key word: altered variants of V. cholerae biovar eltor, production of cholera toxin, copy number of ctxAB genes, sequencing of promoter region.
doi:10.21055/0370-1069-2012-1(111)-57-61 fatcat:4lpyin7uwfgevmsl3tbmrbudam