Nucleotide sequence of the gene encoding a repressor for the cytochrome P-450cam hydroxylase operon on the Pseudomonas putida CAM plasmid

Abstract

The camR gene of Pseudomonas putida encodes a repressor which regulates expression of the cytochrome P-450cam hydroxylase operon (camDCAB). We determined the nucleotide sequence of 1134 continuous base pairs, including the camR gene. When comparing the amino acid sequence deduced from the open reading frame of the gene sequence with that of amino-terminal five residues of the cam repressor, purified from Pseudomonas putida, we found that the camR gene encodes a protein of 186 amino acids, with a molecular mass of 20.4 kDa. The start codon for the cam repressor is the rare initiation codon GTG. The cam repressor predicted from the camR sequence contained a region similar to that seen in other DNA-binding proteins.