FIG. 6.
Survival of strain MC58, the Δhfq mutant, and the Δhfq_C complemented mutant in ex vivo whole blood (A) and serum (B) assays and an in vivo infant rat model (C). There was a reduced level of bacteremia with the Δhfq mutant in an infant rat infection model. Groups of animals were inoculated with two initial doses (approximately 103 and 105 CFU; specific levels of the initial inoculum were determined in each case and are indicated on the x axis), and bacterial counts for the wild type (diamonds) and the Δhfq mutant (triangles) recovered from the blood of each animal were determined after an 18-h period. The P values for comparisons of the levels of the wild type and the Δhfq mutant recovered with initial doses of 103 and 105 CFU are 0.0007 and 0.0057, respectively.