FIG 2.

NtrC negatively regulates vpsR, vpsT, and hapR expression. (A) Expression of PvpsR-luxCADBE, PvpsT-luxCADBE, and PhapR-luxCADBE in the WT and ΔntrC strains at the exponential growth phase. The graph represents the averages and standard deviations of RLU obtained from three technical replicates from two independent biological samples. RLU are reported in luminescence counts per minute per milliliter per OD₆₀₀. A two-tailed unpaired t test with Welch's correction was used to compare expression levels between the WT and deletion mutants. **, P < 0.01; ****, P < 0.0001. (B) Western blot analysis of HapR production in the WT and ΔntrC strains during the exponential growth phase (OD₆₀₀ of 0.3). Equal amounts of total protein (determined by a BCA assay) were loaded onto an SDS–12% polyacrylamide gel. The abundance of RNA polymerase (RNAP) was used as a loading control.