Cloning and Nucleotide Sequences of NADH-Putidaredoxin Reductase Gene (camA) and Putidaredoxin Gene (camB) Involved in Cytochrome P-450cam Hydroxylase of Pseudomonas putida1

Abstract

Pseudomonas putida PpGl, which carries the CAM plasmid encoding enzymes involved in the degradation pathway of D-camphor, can utilize D-camphor as a sole carbon source. Cytochrome P-450cam and related enzymes participate in the early oxidation steps of D-camphor degradation metabolism. We cloned from a HindIII DNA library of PpGl a 2.9 kbp CAM segment which carries the major part of camA gene encoding NADH-putidaredoxin reductase and the entire camB gene encoding putidaredoxin. The 2.9 kbp CAM segment was adjacent to the 4.27 kbp HindIII CAM segment which has been previously cloned (Koga et al. (1986) J. BacterioL 166, 1089–1095). Thus, the total 7.17 kbp HindIII CAM directed all the genes responsible for early steps of D-camphor degradation, i.e. 5-exo-hydroxycamphor dehydrogenase (camD gene), cytochrome P-450cam (camC), NADH-putidaredoxin reductase (camA), and putidaredoxin (camB). These cam genes form an operon, camDCAB, and are under negative control by the gene camR located immediately upstream from the camD gene. The total number of amino acids deduced from the nucleotide sequence is 422 for putidaredoxin reductase, and 106 for putidaredoxin.