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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">microbe</journal-id><journal-title-group><journal-title xml:lang="ru">Проблемы особо опасных инфекций</journal-title><trans-title-group xml:lang="en"><trans-title>Problems of Particularly Dangerous Infections</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">0370-1069</issn><issn pub-type="epub">2658-719X</issn><publisher><publisher-name>Russian Research Anti-Plague Institute “Microbe”</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.21055/0370-1069-2022-3-151-157</article-id><article-id custom-type="elpub" pub-id-type="custom">microbe-1737</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>ОРИГИНАЛЬНЫЕ СТАТЬИ</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>ORIGINAL ARTICLES</subject></subj-group></article-categories><title-group><article-title>Сравнительный анализ экспрессии основных генов вирулентности у различных штаммов Vibrio сholerae О1</article-title><trans-title-group xml:lang="en"><trans-title>Comparative Analysis of Expression of the Main Virulence Genes in Various Vibrio cholerae О1 Strains</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-5759-3765</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Челдышова</surname><given-names>Н. Б.</given-names></name><name name-style="western" xml:lang="en"><surname>Cheldyshova</surname><given-names>N. B.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Челдышова Надежда Борисовна</p><p>410005, Саратов, ул. Университетская, 46</p></bio><bio xml:lang="en"><p>Nadezhda B. Cheldyshova</p><p>46, Universitetskaya St., Saratov, 410005</p></bio><email xlink:type="simple">rusrapi@microbe.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Девдариани</surname><given-names>З. Л.</given-names></name><name name-style="western" xml:lang="en"><surname>Devdariani</surname><given-names>Z. L.</given-names></name></name-alternatives><bio xml:lang="ru"><p>410005, Саратов, ул. Университетская, 46</p></bio><bio xml:lang="en"><p>46, Universitetskaya St., Saratov, 410005</p></bio><email xlink:type="simple">rusrapi@microbe.ru</email><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>ФКУН «Российский научно-исследовательский противочумный институт «Микроб»</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Russian Research Anti-Plague Institute “Microbe”</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2022</year></pub-date><pub-date pub-type="epub"><day>30</day><month>10</month><year>2022</year></pub-date><volume>0</volume><issue>3</issue><fpage>151</fpage><lpage>157</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Челдышова Н.Б., Девдариани З.Л., 2022</copyright-statement><copyright-year>2022</copyright-year><copyright-holder xml:lang="ru">Челдышова Н.Б., Девдариани З.Л.</copyright-holder><copyright-holder xml:lang="en">Cheldyshova N.B., Devdariani Z.L.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://journal.microbe.ru/jour/article/view/1737">https://journal.microbe.ru/jour/article/view/1737</self-uri><abstract><p>Цель – сравнительное изучение экспрессии основных генов вирулентности у штаммов Vibrio cholerae классического биовара, типичных и генетически измененных штаммов V. cholerae биовара Эль Тор.</p><sec><title>Материалы и методы</title><p>Материалы и методы. В качестве модельных использовали природные токсигенные штаммы V. cholerae О1 классического биовара (J89, Пакистан, 1969 г.), типичного (М-887, Астрахань, 1970 г.) и генетически измененного (301, Таганрог, 2011 г.) штаммов биовара Эль Тор. Штаммы выращивали в оптимальных для продукции холерного токсина и токсинкорегулируемых пилей условиях. Исследование роста штаммов проводили на бульоне LB при комнатной температуре с определением количества клеток на спектрофотометре Biowave DNA (Biochrome Ltd., Великобритания). Определение экспрессии генов осуществляли с помощью ПЦР в реальном времени с обратной транскрипцией.</p></sec><sec><title>Результаты и обсуждение</title><p>Результаты и обсуждение. Изучена экспрессия структурных (ctxA, tcpA) и регуляторных (toxR, toxT, tcpP, tcpH) генов вирулентности у штаммов холерного вибриона классического биовара, типичного и генетически измененного штаммов биовара Эль Тор. Выявлены значительные различия по времени и уровню максимальной экспрессии указанных генов у штаммов классического и Эль Тор биоваров. Установлено, что экспрессия генов ctxA и toxR у штамма геноварианта достигала своего максимума на 1–3 ч раньше других штаммов. При этом уровень экспрессии гена ctxA соответствовал уровню классического штамма. Максимальная экспрессия гена toxR у штамма геноварианта была выше, чем у типичного Эль Тор и классического штаммов, а также имела четкую обратную корреляцию с экспрессией гена ctxA. Экспрессия генов tcpA, toxT и tcpH у штамма классического биовара достигала максимума на 1–2 ч раньше, чем у штаммов биовара Эль Тор. Указанные различия следует учитывать при проведении научно-исследовательских работ, связанных с изучением экспрессии основных генов вирулентности.</p></sec></abstract><trans-abstract xml:lang="en"><p>The aim of the work was a comparative study of the expression of the main virulence genes in Vibrio cholerae strains of the classical biovar, typical and genetically modified strains of V. cholerae, El Tor biovar.</p><sec><title>Materials and methods</title><p>Materials and methods. Natural toxigenic strains of V. cholerae O1, classical biovar (J89, Pakistan, 1969), typical (M-887, Astrakhan, 1970) and genetically modified (301, Taganrog, 2011) strains of the El Tor biovar were used as model ones. The strains were grown under optimum conditions for the production of cholera toxin and toxin-coregulated pili. The assessment of strain growth was carried out in LB broth at room temperature with determination of the cells number on a Biowave DNA spectrophotometer (Biochrome Ltd., UK). Determination of gene expression was performed using real-time PCR with reverse transcription.</p></sec><sec><title>Results and discussion</title><p>Results and discussion. The expression of structural (ctxA, tcpA) and regulatory (toxR, toxT, tcpP, tcpH) virulence genes has been investigated in V. cholerae strains of the classical biovar, typical and genetically modified strains of the El Tor biovar. Significant differences have been revealed in terms of time and level of maximum expression of these genes in strains of classical and El Tor biovars. It was found that ctxA and toxR genes expression in the genovariant strain reached its maximum 1–3 h earlier than in the other strains. At the same time, the level of ctxA gene expression corresponded to the level of the classical strain. The maximum expression of the toxR gene in the genovariant strain was higher than in typical El Tor and classical strains, and also had a clear inverse correlation with ctxA gene expression. Expression of the tcpA, toxT, and tcpH genes in the classical biovar strain reached its maximum 1–2 h earlier than in the El Tor biovar strains. These differences should be taken into account when conducting research work related to the study of the expression of the main virulence genes.</p></sec></trans-abstract><kwd-group xml:lang="ru"><kwd>холерный вибрион</kwd><kwd>геноварианты</kwd><kwd>экспрессия генов вирулентности</kwd></kwd-group><kwd-group xml:lang="en"><kwd>Vibrio cholerae</kwd><kwd>genovariants</kwd><kwd>expression of virulence genes</kwd></kwd-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Karaolis D.K., Somara S., Maneval D.R. Jr., Johnson J.A., Kaper J.B. A bacteriophage encoding a pathogenicity island, a type-IV pilus and a phage receptor in cholera bacteria. Nature. 1999; 399(6734):375–9. 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