Transcriptional repression mediated by LysR-type regulator CatR bound at multiple binding sites

The enzymes responsible for benzoate catabolism in Pseudomonas putida are encoded by the catBCA operon which requires the transcription regulator CatR and an inducer. CatR has been shown to bind to two sites in the promoter region of the operon. A third binding region within the catB structural gene has been identified. This region is designated as the internal binding site and functions as a cis-acting repressor based on site-directed mutagenesis studies.