{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,20]],"date-time":"2026-09-20T11:45:49Z","timestamp":1789904749037,"version":"4.0.1"},"reference-count":21,"publisher":"Springer Science and Business Media LLC","issue":"1","content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["BMC Res Notes"],"published-print":{"date-parts":[[2012,12]]},"abstract":"<jats:title>Abstract<\/jats:title>\n          <jats:sec>\n            <jats:title>Background<\/jats:title>\n            <jats:p>\n              <jats:italic>Vibrio cholerae<\/jats:italic> causes the diarrheal disease cholera and utilizes different survival strategies in aquatic environments. <jats:italic>V. cholerae<\/jats:italic> can survive as free-living or in association with zooplankton and can build biofilm and rugose colonies. The bacterium expresses cholera toxin (CT) and toxin-coregulated pilus (TCP) as the main virulence factors. These factors are co-regulated by a transcriptional regulator ToxR, which modulates expression of outer membrane proteins (OmpU) and (OmpT). The aims of this study were to disclose the role of ToxR in expression of OmpU and OmpT, biofilm and rugose colony formation as well as in association with the free-living amoeba <jats:italic>Acanthamoeba castellanii<\/jats:italic> at different temperatures.<\/jats:p>\n          <\/jats:sec>\n          <jats:sec>\n            <jats:title>Results<\/jats:title>\n            <jats:p>The <jats:italic>toxR<\/jats:italic> mutant <jats:italic>V. cholerae<\/jats:italic> produced OmpT, significant biofilm and rugose colonies compared to the wild type that produced OmpU, decreased biofilm and did not form rugoes colonies at 30\u00b0C. Interestingly, neither the wild type nor <jats:italic>toxR<\/jats:italic> mutant strain could form rugose colonies in association with the amoebae. However, during the association with the amoebae it was observed that <jats:italic>A. castellanii<\/jats:italic> enhanced survival of <jats:italic>V. cholerae<\/jats:italic> wild type compared to <jats:italic>toxR<\/jats:italic> mutant strain at 37\u00b0C.<\/jats:p>\n          <\/jats:sec>\n          <jats:sec>\n            <jats:title>Conclusions<\/jats:title>\n            <jats:p>ToxR does seem to play some regulatory role in the OmpT\/OmpU expression shift, the changes in biofilm, rugosity and survival with <jats:italic>A. castellanii<\/jats:italic>, suggesting a new role for this regulatory protein in the environments.<\/jats:p>\n          <\/jats:sec>","DOI":"10.1186\/1756-0500-5-33","type":"journal-article","created":{"date-parts":[[2012,1,17]],"date-time":"2012-01-17T07:33:26Z","timestamp":1326785606000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["ToxR of Vibrio cholerae affects biofilm, rugosity and survival with Acanthamoeba castellanii"],"prefix":"10.1186","volume":"5","author":[{"given":"Soni P","family":"Valeru","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sun N","family":"Wai","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amir","family":"Saeed","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gunnar","family":"Sandstr\u00f6m","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hadi","family":"Abd","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2012,1,16]]},"reference":[{"issue":"4","key":"1362_CR1","doi-asserted-by":"publisher","first-page":"141","DOI":"10.3201\/eid0104.950408","volume":"1","author":"RV Tauxe","year":"1995","unstructured":"Tauxe RV, Mintz ED, Quick RE: Epidemic cholera in the new world: translating field epidemiology into new prevention strategies. 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