Critical nucleotides in the interaction of CatR with the pheBA promoter: conservation of the CatR-mediated regulation mechanisms between the pheBA and catBCA operons.

The promoter of the plasmid-borne pheBA genes encoding enzymes for phenol degradation resembles the catBCA promoter and is activated by CatR, the regulator of the chromosomally encoded catechol-degradative catBCA genes in Pseudomonas putida. In this study, site-directed mutagenesis of the pheBA promoter region was performed. The interrupted inverted repeat sequence of the CatR recognition binding site (RBS) of the pheBA promoter is highly homologous to that of the catBCA promoter.