Author:
Pezoa David,Blondel Carlos J,Silva Cecilia A,Yang Hee-Jeong,Andrews-Polymenis Helene,Santiviago Carlos A,Contreras Inés
Abstract
Abstract
The type VI secretion system (T6SS) is a virulence factor for many Gram-negative bacteria. Salmonella genus harbors five phylogenetically distinct T6SS loci encoded in Salmonella Pathogenicity Islands (SPIs) SPI-6, SPI-19, SPI-20, SPI-21 and SPI-22, which are differentially distributed among serotypes. The T6SSs encoded in SPI-6 and SPI-19 contribute to pathogenesis of serotypes Typhimurium and Gallinarum in mice and chickens, respectively. Salmonella Dublin is a pathogen restricted to cattle where it causes a systemic disease. Also, it can colonize other hosts such as chickens and mice, which can act as reservoirs of this serotype. Salmonella Dublin harbors the genes for both T6SSSPI-6 and T6SSSPI-19. This study has determined the contribution of T6SSSPI-6 and T6SSSPI-19 to host-colonization by Salmonella Dublin using avian and murine models of infection. Competitive index experiments showed that, a mutant strain lacking both T6SSs (∆T6SSSPI-6/∆T6SSSPI-19) presents a strong colonization defect in cecum of chickens, similar to the defect observed for the ∆T6SSSPI-6 mutant, suggesting that this serotype requires a functional T6SSSPI-6 for efficient colonization of the avian gastrointestinal tract. Colonization of mice was also defective, although to a lesser extent than in chickens. In contrast, the T6SSSPI-19 was not necessary for colonization of either chickens or mice. Transfer of T6SSSPI-6, but not T6SSSPI-19, restored the ability of the double mutant to colonize both animal hosts. Our data indicate that Salmonella Dublin requires only the T6SSSPI-6 for efficient colonization of mice and chickens, and that the T6SSSPI-6 and T6SSSPI-19 are not functionally redundant.
Publisher
Springer Science and Business Media LLC
Reference30 articles.
1. Grimont PD, Weill FX: World Health Organization Collaborating Centre for Reference and Research on Salmonella. Antigenic formulae of the Salmonella serovars. 2007, Paris, France: Pasteur Institute, 9
2. Baumler AJ, Tsolis RM, Ficht TA, Adams LG: Evolution of host adaptation in Salmonella enterica. Infect Immun. 1998, 66: 4579-4587.
3. Wray C, Sojka WJ: Reviews of the progress of dairy science: bovine salmonellosis. J Dairy Res. 1977, 44: 383-425. 10.1017/S0022029900020355.
4. Uzzau S, Brown DJ, Wallis T, Rubino S, Leori G, Bernard S, Casadesus J, Platt DJ, Olsen JE: Host adapted serotypes of Salmonella enterica. Epidemiol Infect. 2000, 125: 229-255. 10.1017/S0950268899004379.
5. Nielsen TD, Kudahl AB, Ostergaard S, Nielsen LR: Gross margin losses due to Salmonella Dublin infection in Danish dairy cattle herds estimated by simulation modelling. Prev Vet Med. 2013, 111: 51-62. 10.1016/j.prevetmed.2013.03.011.
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