Figure 5.
ApaH, BioB, and ArgF affect eptA promoter activity in a ColRS-independent manner. (a) PeptA promoter activity (area under the normalized luminescence curves) in PAO1 PeptA::lux and its deleted apaH, bioB, or argF derivatives, cultured in LB supplemented with different concentrations of ZnCl2. (b) PeptA promoter activity (area under the normalized luminescence curves) in the above-mentioned strains and in isogenic deletion mutants lacking the colRS genes, cultured in LB. Values are the mean (±SD) of three independent assays. Asterisks (*) indicate a statistically significant increase in promoter activity with respect to the parental strain cultured in the presence of the same ZnCl2 concentration, according to the unpaired t test (p < 0.01).