Journal of microbiology, epidemiology and immunobiologyJournal of microbiology, epidemiology and immunobiology0372-93112686-7613Central Research Institute for Epidemiology37810.36233/0372-9311-2019-2-25-30Comparative analysis of adaptation properties in typical and genetically altered Vibrio cholerae El Tor strainsZadnovaS. P.Saratov.fake@neicon.ruKritskyA. A.Saratov.fake@neicon.ruPlekhanovN. A.Saratov.fake@neicon.ruCheldyshovaN. B.Saratov.fake@neicon.ruSmirnovaN. I.Saratov.fake@neicon.ruRussian Research Institute for Plague Cоntrol «Microbe»2207201996225302208201922082019Copyright © 2019, Zadnova S.P., Kritsky A.A., Plekhanov N.A., Cheldyshova N.B., Smirnova N.I.2019<p class="MsoNormal"><span style="font-size: 14.0pt; line-height: 107%; mso-ansi-language: EN-US;" lang="EN-US">Aim. Study of biological properties in natural strains of genovariants of V. cholerae biovar El Tor, affecting their adaptation capacities under nutrient deficiency while comparing them with typical strains. Materials and methods. Competitive sampling was carried out through plating a mixture of cells of the two strains under investigation into autoclaved river water. Growth rate was evaluated through the optic density values. Gene expression was studied applying RT-PCR with designed primers and probes. Results. It is established that during combined cultivation of V. cholerae El Tor typical strains and genovariants under the shortage of nutrient substances (autoclaved river water), at room temperature, the level of survivability in genetically altered strains is higher than in typical strains, which points to their expressed adaptation advantages over the typical ones under the stated conditions. It is demonstrated that selective benefits of genovariant strains are provided by higher cell growth rate and increased rpoS gene expression. Conclusion. Obtained have been new data on the ability of bacterial strains of V. cholerae El Tor genovariants to rapidly grow and better express global regulator of stress response, rpoS gene, which, probably, contributes to their enhanced adaptation not only under nutrient deficiency, but under the influence of other stress factors too.</span></p>typical strains and strains of genovariants of Vibrio cholerae O1biovar El Torcompetitive samplinggrowth rateRT-PCRrpoS gene expressionтипичные штаммы и штаммы геновариантов Vibrio cholerae О1 серогруппы биовара El Torконкурентная пробаскорость ростаОТ-ПЦРэкспрессия гена rpoS[1. Бароян О.В. Холера Эль-Тор. 2 изд. перераб. и доп. М., Медицина, 1971.][2. Заднова С.П., Шашкова А.В., Краснов Я.М., Смирнова Н.И. Фенотипический и генетический анализ измененных вариантов Vibrio cholerae биовара эльтор. Пробл. особо опасных инф. 2012, 1:57-61.][3. Заднова С.П., Плеханов Н.А., Крепостнова И.М., Ерохин П.С., Смирнова Н.И. Влияние осмотического и оксидативного стрессов на штаммы геновариантов Vibrio cholerae биовара Эль Тор. Журн. микробиол. 2015, 6:55-62.][4. Заднова С.П., Челдышова Н.Б., Крицкий А.А., Адамов А.К., Девдариани З.Л., Кутырев В.В. Сравнительный анализ метаболизма глюкозы в штаммах Vibrio cholerae биовара Эль Тор. Молекул. генетика, микробиол. и вирусол. 2017, 2:64-69.][5. Ленгелер Й., Древс Г., Шлегель Г. Современная микробиология: Прокариоты. М., Мир, 2005.][6. Смирнова Н.И., Агафонов Д.А., Кульшань Т.А., Краснов Я.М., Кутырев В.В. Микроэволюция возбудителя холеры в современный период. Вестник Российской академии медицинских наук. 2014,7-8:46-53.][7. Freter R., O’Brien P.C., Macsai M.S. Role of chemotaxis in the association of motile bacteria with intestinal mucosa: in vivo studies. Infect. Immun. 1981, 34(1):234-240.][8. Livak K.J., Schmittgen T.D. Analysis of relative gene expression data using real-time quantitative PCR and the 2−ΔΔΧT method. Methods. 2001, 25(4):402-408.][9. Nair G.B., Faruque S.M., Bhuiyan N.A. et al. New variants of Vibrio cholerae O1 biotype El Tor with attributes of the classical biotype from hospitalized patients with acute diarrhea in Bangladesh. J. Clin. Microbiol. 2002, 40(9):3296-3299.][10. Pradhan S., Mallick S.K., Chowdhury R. Vibrio cholerae classical biotype is converted to the viable non-culturable state when cultured with the El Tor biotype. PLOS ONE. 2013, 8: e53504.][11. Reimer A.R., Domselaar G.V., Stroika S. et al. Comparative Genomics of Vibrio cholerae from Haiti, Asia, and Africa Emerg. Infect. Dis. 2011, 17(11): 2113-2121.][12. Son M.S., Megli C.J., Kovacikova G. et al. Characterization of Vibrio cholerae O1 El Tor biotype variant clinical isolates from Bangladesh and Haiti, including a molecular genetic analysis of virulence genes. Infect. Immun. 2011, 49:3739-49.][13. Yildiz F.H., Schoolnik G.K. Role of rpoS in stress survial and virulence of Vibrio cholerae. J. Bacteriol. 1998, 180:773-784.]