SEPARATION OF 3 P450 ISOZYMES FROM LIVER-MICROSOMES OF GILTHEAD SEABREAM TREATED WITH D-NF AND PARTIAL-PURIFICATION OF CYTOCHROME P4501A1

Three distinct cytochrome P450 isozymes, P4501A1, P4502B and an uniden tified P450 isozyme were separated and isolated from beta-NF-treated g ilthead seabream liver microsomes. Cytochrome P4501A1 was partially pu rified from beta-NF-treated gilthead seabream liver microsomes in the presence of detergents Emulgen 913 and cholate and protease inhibitors using two DEAE-cellulose, Porapak Q and two hydroxylapatite column ch romatographies. The overall yield of purified P4501A1 was 1.2% with re spect to microsomal total P450 with a specific content of 3 nmol/mg pr otein. The purified P4501A1 was characterized with respect to spectral , electrophoretic, biocatalytic and immunochemical properties, which a re found to be similar to P4501A1s purified from other teleost species such as trout, scup, cod and perch suggesting that the P450 we have p urified belongs to CYP1A1.