FIG. 3.

Restriction enzyme site protection assays in the presence of structurally dissimilar compounds. In all panels, lane 1 shows molecular weight standards, lane 2 shows the vector (pSup-Test [3.4 nM]) alone digested with SspI, and lane 3 shows pSup-Test in the presence of MarR (2.92 to 3.6 μg or 9.1 to 11.2 μM [assuming the monomeric form of MarR]) digested with SspI. (A) The concentrations of sodium salicylate in lanes 4 to 6 were 0.8, 2, and 5 mM. (B) Lane 4, paraquat at a concentration of 5 mM. (C) Plumbagin (lanes 4 to 6) and 2,4-dinitrophenol (lanes 7 to 9) were tested at concentrations of 0.25, 0.5, and 1 mM; menadione (lanes 10 to 12) was tested at concentrations of 0.8, 2, and 5 mM.