Figure 6

The effect of addition of 100 μM salicylate (SAL), 100 μM 4-nitrobenzoate (4-NB)or both 100 μM salicylate and 100 μM 4-nitrobenzoate simultaneously to E. coli DH5α harbouring WT DntR in the one-plasmid system grown in LB in (a) and grown in M9 in (b). In (c) the effect is shown for cells grown in LB at 0-500 μM salicylate in the presence of 0 (black filled diamonds), 100 μM (grey squares) and 250 μM (black open triangles) 4-nitrobenzoate respectively. The fold of induction was measured as the mean fluorescence for 10 000 cells with inducer(s) added, divided by the mean fluorescence of 10 000 cells from the control culture with only the solvent added after overnight induction. Data are presented as the mean values based on three independent experiments and shown as error bars are the standard deviations.