Analysis of Vibrio cholerae Genotype Stability at Low Temperature and Nutrients Deficiency

Abstract

Objective is an experimental study of the low temperature and nutrient deficiency effects on the stability of Vibrio cholerae El Tor genetic loci complex. Materials and methods. The stability of the genetic loci (i.e. the basic pathogenicity genes; genome fragments containing variable tandem repeats and sites of rare cutting restrictase recognition defining VNTR- and PFGE-profiles of the isolates, accordingly; V. cholerae «housekeeping» genes) of the four Vibrio cholerаe El Tor strains was investigated on the experimental microcosm at different stages of incubation. Results and conclusions. The study demonstrated that clones with altered VNTR- and PFGE-profiles (the detection frequency was 4–8·10–2) were being formed when strains were cultivated under nutrient deficiency and low temperature conditions. Neither changes in the structure of «housekeeping» genes nor loss of pathogenicity genes of the mobile genetic elements were revealed. The findings affirm the probability of analyzed V. cholerae loci alteration occurrence under unfavorable environment conditions. Obtained results should be taken into consideration for interpretation of molecular typing data.