FIG. 2.

(A) Characteristics of the divergent overlapping regB and senC-regA-hvrA operon promoters. The transcription start sites of the regB and senC-regA-hvrA genes are indicated by arrows, with translation start sites of the regB and senC genes also indicated. The −35 and −10 regions are indicated by lines, and the RegA protection regions on both strands are depicted as white letters on a black background. The hypersensitive sites are indicated by asterisks. (B) Comparison of the wild-type and mutant senC-regA-hvrA promoters with the consensus sequence of E. coli ς⁷⁰-type promoters. The R. capsulatus −35 and −10 regions are in capital letters. The most-conserved nucleotides are represented by large uppercase letters, the less-conserved nucleotides are represented by smaller uppercase letters, and the least-conserved nucleotides for E. coli ς⁷⁰ are represented by lowercase letters, with conservation between E. coli and B. capsulatus promoters highlighted by lines. The numbers below the white-on-black letters indicate the sites of promoter mutations in strains SD01-M52 and SD01-M08.