Fig 6.

Promoter activities of the serially deleted upstream regions of ald in M. smegmatis. The ald promoter activities were determined by using ald::lacZ transcriptional fusions with 5′-nested deletions of the ald upstream region. The DNA fragments cloned into pNC consist of a shared 105-bp 5′ portion of ald and ald upstream regions in the different lengths denoted above the schematic diagrams (218, 153, and 109 bp). The relative positions and the presence or absence of the O1, O2, and O3 sites in the transcriptional fusions are indicated by the arrows. M. smegmatis wild-type strains harboring the transcriptional fusions were grown aerobically in the presence (+Ala) or absence (−Ala) of l-alanine, and β-galactosidase activities were determined. All values provided are the averages of results from two independent determinations. Error bars indicate the deviations from the means.