LacZ reporter assays in wild-type and rpoN mutant strains showed that β-galactosidase activity was highly reduced (≅75%) in the mutant. Site-directed mutagenesis in the putative −12 element reduced pchP expression by 95%. The pchP transcriptional start site was determined by 5' RACE experiment. The presence of TSS 14 nucleotides downstream of the putative σ54 −12 element, provided further evidence that this promoter was transcribed by this sigma factor. Additionally, a sequence resembling an IHF binding site was identified in the pchP promoter region.
Regulated genes for each binding site are displayed below. Gene regulation diagrams show binding sites, positively-regulated genes, negatively-regulated genes, both positively and negatively regulated genes, genes with unspecified type of regulation. For each indvidual site, experimental techniques used to determine the site are also given.
|Site sequence||Regulated genes||Gene diagram||Experimental techniques||TF function||TF type|