DNase I footprinting demonstrated and localized the binding sites of PtxR to the toxA, kgu and gad promoter regions. EMSA confirmed this binding to the three promoters. Isothermal calorimetry assays identified the binding of PtxR to it’s targets was caused by favorable enthalpy conditions. PtoxA::lacZ ad Pkgu::lacZ transcriptional fusions using a ptxR knockout mutant showed decreased transcription levels, verifying the role of PtxR as an activator of toxA and kgu.
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|
|CGGCCCGCCG||PA2260, PA2261, PA2262, PA2263,||
|CGGCGCGCCG||PA2264, PA2265, PA2266||