Figure 4

Promoter activity of msaA , msaB , and msaC at three growth phases. Putative promoters were fused to promoter-less luxAB genes and introduced into the wild type strain USA300 LAC. Luciferase activity was measured at three growth phases (early, mid and late exponential). The vector pCN58 containing luxAB without a promoter was used as a negative control. sarAP1 and serine protease promoters were used as positive controls. Results represent means of three independent experiments where each measurement was done in triplicates. Standard error bars are shown.