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http://purl.uniprot.org/citations/3079764http://www.w3.org/1999/02/22-rdf-syntax-ns#typehttp://purl.uniprot.org/core/Journal_Citation
http://purl.uniprot.org/citations/3079764http://www.w3.org/1999/02/22-rdf-syntax-ns#typehttp://purl.uniprot.org/core/Journal_Citation
http://purl.uniprot.org/citations/3079764http://www.w3.org/2000/01/rdf-schema#comment"Two forms of cytochrome P-450 (P-450), designated P-450MP-1 and P-450MP-2, were purified to electrophoretic homogeneity from human liver microsomes on the basis of mephenytoin 4-hydroxylase activity. Purified P-450MP-1 and P-450MP-2 contained 12-17 nmol of P-450/mg of protein and had apparent monomeric molecular weights of 48,000 and 50,000, respectively. P-450MP-1 and P-450MP-2 were found to be very similar proteins as judged by chromatographic behavior on n-octylamino-Sepharose 4B, hydroxylapatite, and DEAE- and CM-cellulose columns, spectral properties, amino acid composition, peptide mapping, double immunodiffusion analysis, immunoinhibition, and N-terminal amino acid sequences. In vitro translation of liver RNA yielded polypeptides migrating with P-450MP-1 or P-450MP-2, depending upon which form was in each sample, indicating that the two P-450s are translated from different mRNAs. When reconsituted with NADPH-cytochrome-P-450 reductase and L-alpha-dilauroyl-sn-glyceryo-3-phosphocholine, P-450MP-1 and P-450MP-2 gave apparently higher turnover numbers for mephenytoin 4-hydroxylation than did the P-450 in the microsomes. The addition of purified rat or human cytochrome b5 to the reconstituted system caused a significant increase in the hydroxylation activity; the maximum stimulation was obtained when the molar ratio of cytochrome b5 to P-450 was 3-fold. Rabbit anti-human cytochrome b5 inhibited NADH-cytochrome-c reductase and S-mephenytoin 4-hydroxylase activities in human liver microsomes. In the presence of cytochrome b5, the Km value for S-mephenytoin was 1.25 mM with all five purified cytochrome P-450s preparations, and Vmax values were 0.8-1.25 nmol of 4-hydroxy product formed per min/nmol of P-450. P-450MP is a relatively selective P-450 form that metabolizes substituted hydantoins well. Reactions catalyzed by purified P-450MP-1 and P-450MP-2 preparations and inhibited by anti-P-450MP in human liver microsomes include S-mephenytoin 4-hydroxylation, S-nirvanol 4-hydroxylation, S-mephenytoin N-demethylation, and diphenylhydantoin 4-hydroxylation. Thus, at least two very similar forms of human P-450 are involved in S-mephenytoin 4-hydroxylation, an activity which shows genetic polymorphism."xsd:string
http://purl.uniprot.org/citations/3079764http://purl.org/dc/terms/identifier"doi:10.1016/s0021-9258(17)36183-5"xsd:string
http://purl.uniprot.org/citations/3079764http://purl.org/dc/terms/identifier"doi:10.1016/s0021-9258(17)36183-5"xsd:string
http://purl.uniprot.org/citations/3079764http://purl.uniprot.org/core/author"Shimada T."xsd:string
http://purl.uniprot.org/citations/3079764http://purl.uniprot.org/core/author"Shimada T."xsd:string
http://purl.uniprot.org/citations/3079764http://purl.uniprot.org/core/author"Misono K.S."xsd:string
http://purl.uniprot.org/citations/3079764http://purl.uniprot.org/core/author"Misono K.S."xsd:string
http://purl.uniprot.org/citations/3079764http://purl.uniprot.org/core/author"Guengerich F.P."xsd:string
http://purl.uniprot.org/citations/3079764http://purl.uniprot.org/core/author"Guengerich F.P."xsd:string
http://purl.uniprot.org/citations/3079764http://purl.uniprot.org/core/date"1986"xsd:gYear
http://purl.uniprot.org/citations/3079764http://purl.uniprot.org/core/date"1986"xsd:gYear
http://purl.uniprot.org/citations/3079764http://purl.uniprot.org/core/name"J. Biol. Chem."xsd:string
http://purl.uniprot.org/citations/3079764http://purl.uniprot.org/core/name"J. Biol. Chem."xsd:string
http://purl.uniprot.org/citations/3079764http://purl.uniprot.org/core/pages"909-921"xsd:string
http://purl.uniprot.org/citations/3079764http://purl.uniprot.org/core/pages"909-921"xsd:string
http://purl.uniprot.org/citations/3079764http://purl.uniprot.org/core/title"Human liver microsomal cytochrome P-450 mephenytoin 4-hydroxylase, a prototype of genetic polymorphism in oxidative drug metabolism. Purification and characterization of two similar forms involved in the reaction."xsd:string
http://purl.uniprot.org/citations/3079764http://purl.uniprot.org/core/title"Human liver microsomal cytochrome P-450 mephenytoin 4-hydroxylase, a prototype of genetic polymorphism in oxidative drug metabolism. Purification and characterization of two similar forms involved in the reaction."xsd:string
http://purl.uniprot.org/citations/3079764http://purl.uniprot.org/core/volume"261"xsd:string
http://purl.uniprot.org/citations/3079764http://purl.uniprot.org/core/volume"261"xsd:string
http://purl.uniprot.org/citations/3079764http://www.w3.org/2004/02/skos/core#exactMatchhttp://purl.uniprot.org/pubmed/3079764
http://purl.uniprot.org/citations/3079764http://www.w3.org/2004/02/skos/core#exactMatchhttp://purl.uniprot.org/pubmed/3079764
http://purl.uniprot.org/citations/3079764http://xmlns.com/foaf/0.1/primaryTopicOfhttps://pubmed.ncbi.nlm.nih.gov/3079764
http://purl.uniprot.org/citations/3079764http://xmlns.com/foaf/0.1/primaryTopicOfhttps://pubmed.ncbi.nlm.nih.gov/3079764
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