Histidine residues in rabbit liver microsomal cytochrome P-450 2B4 control electron transfer from NADPH-cytochrome P-450 reductase and cytochrome b5
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منابع مشابه
Histidine residues in rabbit liver microsomal cytochrome P-450 2B4 control electron transfer from NADPH-cytochrome P-450 reductase and cytochrome b5.
Treatment of cytochrome P-450 2B4 (P-450 2B4) with diethylpyrocarbonate to introduce 10-11 equivalents of acylating agent per polypeptide chain resulted in the selective derivatization of histidine residues characterized by differential susceptibility toward the modifier. Second-derivative spectral analysis as well as fluorescence measurements disproved gross alterations in P-450 2B4 structure ...
متن کاملPurified Liver Microsomal NADPH-Cytochrome P-450 Reductase
NADPH-cytochrome P-450 reductase was isolated from liver microsomes of phenobarbital-induced rats. The enzyme exhibits an apparent minimal molecular weight of 76,000 as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and contains 1 molecule each of FMN and FAD. Trypsin treatment of the reductase yields an enzyme with an apparent minimal molecular weight of 69,000 which r...
متن کاملPurified Liver Microsomal NADPH-Cytochrome P-450 Reductase
NADPH-cytochrome P-450 reductase was isolated from liver microsomes of phenobarbital-induced rats. The enzyme exhibits an apparent minimal molecular weight of 76,000 as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and contains 1 molecule each of FMN and FAD. Trypsin treatment of the reductase yields an enzyme with an apparent minimal molecular weight of 69,000 which r...
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In rat liver there appear to be significant differences between lobes in the concentration of individual cytochrome P-450 isozymes (Sumner and Lodola, Biochem Pharmacol 36: 391-393, 1987). Because studies in patients often rely on small pieces of liver obtained from diverse anatomical locations, it seemed important to determine if the cytochromes P-450 were also heterogeneously distributed in h...
متن کاملInteraction of liver microsomal cytochrome P-450 and NADPH-cytochrome P-450 reductase in the presence and absence of lipid.
Phospholipid has been reported to be necessary for optimal catalytic activity of a number of mammalian cytochrome P-450 (P-450) systems. We also confirm that a number of individual phospholipids and mixtures, used as soluble monomers or phospholipid vesicles, show activation of 7-ethoxycoumarin O-deethylase activity by an enzyme system composed of rat liver microsomal P-450PB-B and NADPH-P-450 ...
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ژورنال
عنوان ژورنال: Biochemical Journal
سال: 1996
ISSN: 0264-6021,1470-8728
DOI: 10.1042/bj3180857