FIG. 3.

Analysis of the ropB promoter. The importance of sequences in the speB-ropB region for transcription of the ropB promoter was evaluated as described in the legend to Fig. 2. The number at the right end of each truncation indicates the 5′-terminal nucleotide relative to the first nucleotide of the start codon for ropB. Bent arrows represent 5′ ends of the speB transcripts and are numbered relative to the start codon of ropB. Alkaline phosphatase activity is shown as a percentage of that produced by the full-length intergenic region (pROP10). One hundred percent activity for pROP10 was 32 U, calculated as enzyme units per unit of optical density at 600 nm as described by Brinkman and Beckwith (6). All other designations are the same as those described for Fig. 2.