FIG 6.
CmrR autoregulation occurs at the TSS4 promoter and is enhanced by the cmr-ON switch sequence. Alkaline phosphatase reporter activity for regions of the cmr 5′ untranslated region (UTR) containing one or more putative promoters in C. difficile with ATc-inducible Ptet::cmrR at an ectopic site. (Left) Diagrams of the plasmid-borne reporter fusions carried by the strain. (Right) AP reporter activity after growth with or without 10 ng/mL ATc to induce cmrR expression (Fig. S4). Shown are means and standard deviations from three independent experiments. ****, P < 0.0001; two-way ANOVA and Sidak’s posttest.