Initial purification and characterization of hepatic microsomal cytochrome P-450 from BNF-treated perch (Perca fluviatilis).

1. A procedure was developed for isolating and purifying cytochrome P-450 from hepatic microsomes of BNF-treated perch, using modified versions of the methods of Williams and Buhler (1982. Biochim. biophys. Acta 717, 398-404) and Goksøyr (1985. Biochim. biophys. Acta 850, 409-417). 2. Following chromatography on phenyl-Sepharose CL 4B and DEAE-Sepharose CL-6B, the major peaks, fractions b and c, were resolved into five fractions, possibly representing different isoenzymes, by a FPLC with a strong anion exchange column (Mono Q). 3. These fractions have been characterized on the basis of their spectral, electrophoretic and immunological properties. 4. The purified form of cytochrome P-450 in fraction V from perch liver showed a number of similarities to cytochrome P-450c, the major BNF-inducible cytochrome P-450 in cod liver. 5. Therefore we suggest that this purified form of cytochrome P-450 is a BNF-induced form in perch and that it is closely related to the gene subfamily cytochrome P-450 IA1.