Figure 6. Depletion of Clostridia increases colonocyte oxygenation and drives a cytochrome bd-II oxidase-dependent expansion of S. Typhimurium.
Groups of CBA mice were mock-infected or infected intragastrically with a 1:1 mixture of the S. Typhimurium wild type (wt) and a cyxA mutant. At 5, 7 and 10 days after infection, mice were mock-inoculated or inoculated with 17 human Clostridia isolates (C17). (A) The competitive index (CI) in feces or colon contents was determined at the indicated time points. (B–D) Concentrations of butyrate (B), acetate (C) and propionate (D) in cecal contents are shown. (A–D) Bars represent geometric means ± standard error. (E–G) Binding of pimonidazole (red fluorescence) was detected in colonic sections counter stained with DAPI nuclear stain (blue fluorescence). Representative images are shown. *, P < 0.05; ***, P < 0.005; ****, P < 0.001; ns, not statistically significantly different.