FIG.2.

Binding of DtxR to the predicted DtxR boxes. DNA fragments (200 to 400 bp in size; final concentration, 10 to 20 nM) covering promoter regions with putative DtxR binding sites were incubated for 30 min at room temperature without DtxR (left lanes) or with a 50-fold or a 200-fold (labeled with an asterisk) molar excess of purified DtxR protein (dimeric form) (right lanes) before separation by native polyacrylamide (15%) gel electrophoresis and staining with SybrGreen I. DNA fragments (100 to 200 bp) covering the promoter regions of acn, pta, and katA, which do not contain putative DtxR binding sites, served as negative controls.