Promoter-region sequences of seven rrn operons used for construction of the promoter assay vectors.

For construction of the promoter assay vectors of rrn operons, a total of approximately 500 bp-long sequence upstream from 5’ terminus of 16S rRNA gene, as indicated above each DNA lane, were PCR-amplified using specific set of primers (for primer sequences see S1 Table) and inserted into pGRS vector, a modified form of pGRP [28], containing an SD sequence at the junction of GRF-coding sequence. Open box and closed boxes on each probe represent the relative location of UP element and predicted Fis-binding sites, respectively (see Fig 8). Triangles downstream of the UP element indicate two promoters, upstream P1 and downstream P2. The number of Fis sites on the rrnE promoter was suggested to be more than those hitherto identified (see Fig 3). The whole length used for the construction of pGRS vector is described in parenthesis at right-side end of each lane.