FIG. 3.

The AmrZ extended amino terminus is not required for DNA-binding activity. (A and B) Protein activity was analyzed with 5′-FAM-labeled PCR-amplified targets of the algD (A) or amrZ (B) promoter region. Lanes 1 and 6 have no protein. lane 2, wild-type (WT) AmrZ; lane 3, Δ2AmrZ; lane 4, Δ5AmrZ; lane 5, Δ11AmrZ (at 125 nM each). The black arrows on the left indicate free unbound DNA, while the gray arrows indicate the migration of DNA-protein complexes. The fluorescence anisotropy data (see Materials and Methods) were assembled into a table, separated for each target site (Table 1). (C and D) A representative experiment is illustrated for the activator site algD (C) and the high-affinity repressor site amrZ1 (D).