Fig 7.
Mutational analysis of the ABp and ABd binding sites at the breAB promoter. (A) Binding of BreR to the wild-type and mutated (ABpmut and ABdmut) ABp and ABd fragments. EMSA was performed using DIG-dUTP-labeled DNA (10 ng) incubated with 0 (lanes 1, 4, 7, and 10), 50 (lanes 2, 5, 8, and 11), or 250 ng (lanes 3, 6, 9, and 12) of BreR-His6 prior to electrophoresis. (B) Influence of base pair mutations in PbreAB-lacZ expression in various strain backgrounds. β-Galactosidase activity was measured as described for Fig. 6.