ISOLATION OF PLANT CYTOCHROME-P-450 AND NADPH - CYTOCHROME-P-450 REDUCTASE FROM TULIP BULBS (TULIPA-FOSTERIANA L) OXIDIZING XENOBIOTICS

Cytochrome P-450 and NADPH: cytochrome P-450 reductase were solubilize d by detergents from microsomal fraction of tulip bulbs Tulipa fosteri ana L. and purified to electrophoretic homogeneity. The purification w as achieved by anion-exchange column chromatography, hydroxyapatite-co lumn chromatography and affinity chromatography. The two enzyme showed relative molecular weights of about 54,200 and 77,600 for cytochrome P-450 and NADPH: cytochrome P-450 reductase, respectively. The purifie d enzymes were characterized by their absorption spectra and by kineti c characteristics. The interaction with endogeneous as well as exogeno us substrates was studied by differential spectroscopy. Both enzymes i n the presence of dilauroyl phosphatidylcholine and NADPH were able to oxidize xenobiotics (N-nitroso-N-methylaniline and N-nitroso-N-dimeth ylamine) in the reconstitution experiments.