Effect of CTXφ prophage deletion in cholera agent on expression of regulatory genes controlling virulence and biofilm formation
- Authors: Smirnova N.I.1, Agafonov D.A.1, Kul’shan’ T.A.1, Shchelkanova E.Y.1, Krasnov Y.M.1, Lozovsky Y.V.1, Kutyrev V.V.1
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Affiliations:
- Russian Research Anti-Plague Institute Microbe
- Issue: Vol 53, No 3 (2017)
- Pages: 302-313
- Section: Genetics of Microorganisms
- URL: https://journals.rcsi.science/1022-7954/article/view/188153
- DOI: https://doi.org/10.1134/S1022795417020119
- ID: 188153
Cite item
Abstract
This work represents the results of comparative analysis of the nucleotide sequences in the chromosomal region containing CTXφ prophage in isogenic toxigenic (Tox+) and nontoxigenic (Tox–) strains of Vibrio cholerae biovar El Tor. It is shown that spontaneous mutants which have identical Tox– phenotype are formed either owing to the precise elimination of CTXφ prophage from the chromosome (deletion size is 6.9 kb) or owing to imprecise elimination with the additional loss of two other prophages (RS1φ and TLCφ), which are adjacent to CTXφ prophage (deletion size is 17.4 kb). It is revealed that, in the nontoxigenic mutants, CTXφ deletion initiates simultaneous change in several phenotypic properties, which are associated with virulence or biofilm formation, such as colonizing ability, HA/P production, VPS, and motility. For the first time, it is stated that the cause of the pleiotropic effect of the CTXφ deletion is a cascade decrease in the transcription levels of seven regulatory genes (toxR, aphA, tcpP, tcpH, toxT, vpsT, vpsR) which control virulence and biofilm formation processes in the cholera agent.
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About the authors
N. I. Smirnova
Russian Research Anti-Plague Institute Microbe
Author for correspondence.
Email: rusrapi@microbe.ru
Russian Federation, Saratov, 410005
D. A. Agafonov
Russian Research Anti-Plague Institute Microbe
Email: rusrapi@microbe.ru
Russian Federation, Saratov, 410005
T. A. Kul’shan’
Russian Research Anti-Plague Institute Microbe
Email: rusrapi@microbe.ru
Russian Federation, Saratov, 410005
E. Yu. Shchelkanova
Russian Research Anti-Plague Institute Microbe
Email: rusrapi@microbe.ru
Russian Federation, Saratov, 410005
Ya. M. Krasnov
Russian Research Anti-Plague Institute Microbe
Email: rusrapi@microbe.ru
Russian Federation, Saratov, 410005
Yu. V. Lozovsky
Russian Research Anti-Plague Institute Microbe
Email: rusrapi@microbe.ru
Russian Federation, Saratov, 410005
V. V. Kutyrev
Russian Research Anti-Plague Institute Microbe
Email: rusrapi@microbe.ru
Russian Federation, Saratov, 410005