Biofilm formation can increase bacterial resistance to adverse conditions. However, limited information is available regarding the roles of the csgA and bcsA genes involved in biofilm formation and virulence for Salmonella enterica serovar Typhimurium. Here we deleted the csgA and bcsA genes in S. Typhimurium strains S016 and S025 and assessed several aspects of biofilm formation and virulence. The ΔcsgA strains did not produce curli fimbriae and ΔbcsA mutants had decreased cellulose production. The ΔcsgA strains were unable to form biofilms. The ΔcsgA strains also showed decreased adhesion and invasion to HeLa cells and reduced intracellular proliferation in HD11 macrophages. The ΔbcsA mutants had similar adhesion, invasion, and proliferation as compared to the wild-type strains. The ΔcsgA strains were significantly attenuated in the virulence in assays involving oral challenge of one-day-old chickens. These findings clarify the respective roles of csgA and bcsA in biofilm formation and pathogenicity of S. Typhimurium.

To Cite This Article: El Hag M, Feng Z, Su Y, Qin T, Chen S, Peng D and Liu X, 2018. The role of csgA and bcsA genes on biofilm formation and virulence in Salmonella enterica serovar Typhimurium. Pak Vet J, 38(2): 159-164. http://dx.doi.org/10.29261/pakvetj/2018.049