P. putida catalase genes katA and katB were initially selected for study. Catalase activity was monitored in wild-type and oxyR mutant strains, with the mutant strain demonstrating activity 10x in excess of the wild-type. Activity stain gel analysis of katA and katB mirrored these results. The P. putida gene ahpC was selected for investigation when it was determined to share an oxyR-binding motif with katA and katB, based on the E. coli oxyR binding motif. EMSA of katA, katB, and ahpC demonstrated direct binding of oxyR with similar affinity for all three, with specificity confirmed against DNA lacking the proposed binding sites. RT-PCR of katA, katB, and ahpC in oxyR-variable strains was consistent with data from the activity staining gels.
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|