FIGURE 1.
Organization of the region upstream of the fimB open reading frame. A, location of operator sites for NagC (ONC2) and SlyA (OSA1 and OSA2), together with the fimB promoter, are indicated. The regions bound by H-NS for which a match to a consensus H-NS binding site (51) was identified are also shown (H-NS1 to H-NS3). The fim DNA included in the amplicon used for EMSA and DNase I footprinting experiments is likewise indicated (fim03). The NagC binding site ONC2 was reported previously (45). B, wild type nucleotide sequence encompassing OSA1 and OSA2 are boxed. The nucleotide sequences of matches to H-NS binding site consensus are labeled (H-NS2 and H-NS3) and are emphasized in bold text. The mutated sequences designated rm21, rm22, rm35, rm39, and rm40 are shown beneath.