Figure 2.

HapR binds to promoters containing either Motif 1- or Motif 2-binding sites. HapR's ability to bind to various promoters containing either of the two consensus binding sites was determined by EMSA in the presence of poly(dI–dC). Due to differences in HapR-binding affinity, two different sets of HapR protein concentrations were used, as indicated by the color of the wedges above the gel shifts. Solid wedges represent four times more protein than unfilled wedges. Since Motif 1 does not have a set length, promoters containing Motif 1-binding sites of varying lengths were tested, and the length of the putative binding site for each promoter is indicated. Consensus binding sequences that fall between two divergently transcribed genes are labeled with both flanking gene locus numbers. The double bands of vc1181 resulted from the nonspecific labeled PCR products of the vc1181 promoter region.