FIG. 5.

Effect of the putative SarA binding sites on spa promoter activity. Shown are the CAT activities promoted by the −259 promoter fragment (black bars), the −259 promoter fragment with the promoter-proximal SarA box (10) replaced by lacC sequences (white bars), and the −259 fragment with the upstream putative SarA binding site deleted (hatched bars). Host strains are indicated along the y axis. CAT activity is expressed as nanomoles of chloramphenicol acetylated per minute per milligram of cells (dry weight). Values plotted are the means of at least three determinations with the standard deviations.