Objective To investigate the effect of Salmonella typhi(S. typhi) plasmid on the formation of biofilm. Methods Wild-type S. typhi strain carrying plasmid pRST98 was cultured at 301 or 371 for 3 d to determine the optimum temperature of biofilm formation using semi-quantitative method. Then the strain was cultured at 30℃ for 12h, 1d,2d,3d,4d and 5 d to determine the biofilm mature time using semi-quantitative method. Wild-type S. typhi strain carrying plasmid pRST98, pRST98-deletion S. typhi strain and pRST98-complemented S. typhi strain were used and then the biofilm formation ability of these three strains was compared by using crystal violet staining method, semi-quantitative method and scanning electron micrographs. Results The ability of biofilm formation was better at 30℃ , which is the optimum temperature of Salmonella biofilm formation. Biofilm became mature after cultured for 3 d. The ability biofilm formation by wild-type and pRST98-complemented 5. typhi strain to form biofilm was stronger than that of pRST98-deletion S. typhi strain. Conclusion Plasmid pRST98 is closely related to biofilm formation of S. typhi.
NETL
NSTL
维普
万方数据
