GENES FOR 2 HERBICIDE-INDUCIBLE CYTOCHROMES-P-450 FROM STREPTOMYCES-GRISEOLUS

Streptomyces griseolus ATCC 11796 contains two inducible, herbicide-metabolizing cytochromes P-450 previously designated P450(SU1) and P-450(SU2) (P-450CVA1 and P-450CVB1, respectively, using nomenclature of Nebert et al. [D.W. Nebert, M. Adesnik, M.J. Coon, R.W. Estabrook, F.J. Gonzalez, F.P. Guengerich, I.C. Gunsalus, E.F. Johnson, B. Kemper, W. Levin, I.R. Phillips, R. Sato, and M.R. Waterman, DNA 6:1-11, 1987]). Using antibodies directed against cytochrome P-450(SU1), its N-terminal amino acid sequence, and amino acid composition, we cloned the suaC gene encoding cytochrome P-450(SU1). Similar information about the cytochrome P-450(SU2) protein confirmed that a gene cloned by cross-hybridization to the suaC gene was the subC gene encoding cytochrome P-450(SU2). The suaC and subC genes were expressed in Escherichia coli, DNA for both genes was sequences, and the deduced amino acid sequences were compared with that of the well-characterized cytochrome P-450(CAM) from Pseudomonas putida. Both cytochromes P-450(SU1) and P-450(SU2) contain several regions of strong similarity with the amino acid sequence of P-450(CAM), primarily in regions of the protein responsible for attachment and coordination of the heme prosthetic group.