Fig. 3.

dgp promoter inversions. (A) The upstream dgp IR sequences showing a consensus at the bottom in bold. (B) Schematic of the procedure used to demonstrate DNA inversions. (C) EtBr-stained agarose gel of PCR products amplified from B. distasonis chromosome when the internal primer is used with either the upstream or downstream primer. (D) EtBr-stained agarose gels of PCR digestion experiments showing the percentage of organisms with ON and OFF orientations for the invertible dgp promoters from in vitro cultures, from the feces of mice, or from human fecal samples.