Fig 5.

CzcS/CzcR represses PCH biosynthetic gene expression by inhibiting the expression of pchR. (A) Expression of PpchR-lux was measured in the WT and ΔczcR strains when they were cultured in the absence or presence of Zn. (B and C) Expression of PpchD-lux (B) and PpchE-lux (C) was measured in the WT, ΔczcR, ΔpchR, and ΔczcR ΔpchR strains when they were cultured in the presence of Zn. (D) Growth of the WT(EV), ΔczcR(EV), ΔpchR(EV), ΔpchR(pchR), ΔczcR ΔpchR(EV), and ΔczcR ΔpchR(pchR) strains in the presence of 1.0 mM DIP when the strains were pretreated with Zn. (E) Prediction of the CzcR-binding site in the promoter of pchR. (F) EMSAs showed the binding ability of CzcR at the promoter of pchR (PpchR) but not the promoter of pvdRT-opmQ (PpvdR). Statistical significance was calculated compared to the indicated groups based on two-way ANOVA (A) or one-way ANOVA (B and C) (n.s., not significant; **, P < 0.01; ***, P < 0.001).