FIG 3.
Diminished virulence of C. sakazakii due to the absence of hfq in vivo. Two- to 3-day-old rat pups were orally administered a mixture of wild-type C. sakazakii harboring pACYC184 (SK001) and an hfq::kan strain (SK004), with approximately 5 × 108 CFU/ml of each. To determine the bacterial loads in the spleen and liver, the organs were removed aseptically, homogenized at 20 h postinfection, and plated onto selective agar. The CI was calculated as follows: (Δhfqoutput/Δhfqinput)/(WToutput/WTinput). A CI of <1 indicates attenuation of virulence. Each circle or square represents the CI for a single animal in the spleen and liver of each group, respectively. The geometric means of the CIs for all the rat pups are shown as solid lines, and the asterisks indicate significant differences (**, P < 0.05; *, P < 0.1). CI values of less than 1 indicate that hfq::kan (SK004) strains were outcompeted by the wild type (SK001).