Fig 3.

Activity and expression of each MarR variant in complemented SPC107. (A) Effect of each marR mutation on β-galactosidase activity from a marO-lacZ fusion in SPC107. SPC107 was transformed with plasmids pACT7Sp and pET28a carrying marR variants. Cells were grown in the absence of IPTG. The data represent the means ± the standard deviations for at least three independent experiments. Percentages at A = 100 × [LacZ (MarR)/LacZ (no MarR)]_{no salicylate}. Numbers above the bars represent the LacZ (salicylate)/LacZ (no salicylate) ratio for each variant. (B) Western blot analysis using lysates of complemented SPC107 grown in the absence of IPTG. Lysate from cells carrying pACT7Sp and pET28a without insert was used as a negative control (empty vector). Each lane contained 10 μg of cell lysate. MarR was detected using polyclonal anti-MarR antibodies. WT, wild type.