FIG 4.

Regulation of pigA by EepR and epistasis analysis. (A) β-Galactosidase-based expression from the pigA promoter at an OD₆₀₀ of 4. WT, CMS376; crp strain, CMS1687; crp eepR strain, CMS2157; eepR strain, CMS2097; eepR repaired strain, CMS2921. (B) qPCR analysis of the pigA promoter at an OD₆₀₀ of 2. WT, CMS376; crp strain, CMS1687; crp eepR strain, CMS795; eepR strain, CMS2097. (C) EMSA analysis of MBP-EepR interaction with biotin-labeled pigA promoter (P_pigA; 2 ng) in vitro. MBP-EepR produced a gel shift of labeled P_pigA that could be inhibited by an excess of unlabeled P_pigA (P_pigA-UL). Recombinant MBP was not sufficient to produce a gel shift of P_pigA. An asterisk indicates significant difference from the WT by ANOVA with Tukey's posttest.