Intracellular growth of F. tularensis in J774 cells. LVS, the ΔpdpC mutant, the complemented ΔpdpC mutant, or the ΔiglC mutant was used to infect J774 cells for 2 h, after which the monolayers were washed and medium added (corresponds to 0 h). Cells were then incubated for 24 or 48 h before being lysed, serially diluted and plated to estimate the number of CFU. The graph presents a representative experiment out of eight performed. Each bar represents the mean value and the error bars represent the standard deviation. The asterisk indicates that the log10 data differs significantly from LVS (***: P < 0.001). Two-sided Student’s t-test was used to compare means.