FIG. 2.
Phenotype of the ΔRv1931c mutant and complemented strains in a mouse model of infection. BALB/c mice were inoculated intravenously with approximately 5 × 105 CFU of each strain. The survival and multiplication of the M. tuberculosis strains in the lungs and the spleen were determined by CFU counts and are shown for the 1424 wild-type (•), ΔRv1931c (▾), and Rv1931c-complemented (▪) strains. The results for each time point are the means of CFU determinations performed on organs from three mice, and the error bars show the standard deviations. The asterisk indicates that the result is statistically significantly different from that of the wild type by the two-tailed Student t test for groups of unequal variance (P < 0.01), as well as by single-factor analysis of variance (P < 0.01). KO, knockout.