FIG. 5.

Survival of serovar Typhimurium cells in colonies of the rdar morphotype following a 20-min exposure to sodium hypochlorite. A. ATCC 14028 rdar colonies stored for 3 months on plastic were rehydrated and treated with different concentrations of sodium hypochlorite. Each point represents the average number of surviving cells (CFU) per colony and standard errors corresponding to at least two individual colonies. B. Survival of cells from 3-month-old colonies of ATCC 14028, ΔagfD, ΔagfA, and ΔbcsA was compared to that of planktonic cells grown at 37°C for 20 h (stationary phase) after treatment with 60 ppm sodium hypochlorite. Bars represent the average relative survival (log CFU after treatment/log CFU before treatment) and standard errors from at least four individual colonies or aliquots of planktonic cells. CFUs for colonies before treatment are displayed in Table 1; for planktonic cells, the initial values ranged from 4.2 × 10⁸ to 5.5 × 10⁸ CFU.