FIG. 6.

Dependence of open-complex formation at the strR promoter on AdpA, as determined by potassium permanganate footprinting. The ³²P-labeled antisense strand of the strR promoter region (positions −482 to +68) was used. The concentration of AdpA-H in lanes 2 to 7 was 20 nM. Ten nanomolar AdpA equals 8.8 ng of AdpA in a total volume of 20 μl. The concentrations of RNA polymerase (RNP) in lanes 3 to 7 were 5, 15, 50, 150, and 300 nM, respectively. The positions of the thymidines reacted with KMnO₄, corresponding to adenines of the sense strand, were determined using the G+A sequencing ladder (lane GA) as a reference. The nucleotide numbers are shown taking the transcriptional start point as +1.