Figure 5 |. Inhibition of S. aureus colonization by dietary fengycin-producing Bacillus spores in a mouse model.

a, Experimental setup. n=5 mice/group received 200 μl of 10⁸ CFU/ml S. aureus strain ST2196 F12 by oral gavage. On the next and every following second day, they received 200 μl of 10⁸ CFU/ml spores of the B. subtilis wild-type (WT) or its isogenic fenA mutant, also by oral gavage. CFU in the feces were determined two, four, and six days after infection. At the end of the experiment (day seven), CFU in the small and large intestines were determined. The experiment was performed with (b) or without (c) antibiotic pre-treatment. b,c Results. Statistical analysis was performed using Poisson regression versus values obtained with the B. subtilis WT spore samples. *, p<0.0001. Error bars shown the means ±SD. Note no S. aureus were found in the feces or intestines of any mouse challenged with any S. aureus strain receiving Bacillus wild-type spores. The corresponding zero values are plotted on the x-axis of the logarithmic scale. See Extended Data Fig. 5 for the corresponding data using strains USA300 LAC and ST88 JSNZ.