FIG. 5.
Binding of FrtR to the promoter region of frtA. A 32P-labeled 131-bp DNA fragment upstream of frtA was incubated with or without recombinant FrtR protein. Samples in lanes 2 and 3 contained 100 ng and 300 ng of FrtR protein extract, respectively. Samples in lanes 4 to 7 contained 700 ng of FrtR protein extract.