Electron Transport Components of Hepatic Microsomes
نویسنده
چکیده
Components of the hepatic microsomal P-450 hemoprotein electron transfer system (TPNH-cytochrome c reductase and P-450 hemoprotein) and the microsomal cytochrome b5 electron transfer system (DPNH-cytochrome bs reductase and cytochrome bS) were solubilized using Triton N-101 and glycerol, and separated using DEAE-cellulose chromatography. Microsomal aniline hydroxylase activity was reconstituted when the TPNH-cytochrome c reductase fractions and the P-450 hemoprotein fraction were combined. Crossactivities of the TPNH reductases and P-450 hemoproteins were obtained with preparations from phenobarbitaland 3-methylcholanthrene-treated rats. The reconstituted aniline hydroxylase system resembled the native system with respect to turnover number, reducibility of the P-450 hemoprotein component with TPNH, and inhibition with carbon monoxide, p-chloromercuribenzoate, and vitamin &, but differed in its ability to react with type I substrates such as ethylmorphine and aminopyrine.
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