{"title":"Novel sensitive high-performance liquid chromatographic method for assay of coumarin 7-hydroxylation.","authors":"P Soucek","doi":"","DOIUrl":null,"url":null,"abstract":"<p><p>In this paper, a novel HPLC-based method with fluorometric detection of coumarin 7-hydroxylase is presented. The described method provides a time-effective, more sensitive and specific alternative to the previously used spectrofluorometric assay. Using the developed method, metabolism of coumarin in 11 samples of human liver microsomes was evaluated and 1790+/-690 pmol/min/nmol cytochrome P450 (CYP) activity was found. Kinetic parameters and linearity of coumarin 7-hydroxylation were studied in a reconstituted system consisting of recombinant CYP2A6 expressed in Escherichia coli, rat NADPH-CYP reductase and usual components. It was found that a 3.5 to 30 min time of incubation is suitable for estimation of coumarin 7-hydroxylase activity. Observed Km and Vmax values in the CYP2A6 reconstituted system were 1.48+/-0.37 microM and 3360+/-180 pmol product/min/nmol CYP, respectively.</p>","PeriodicalId":15425,"journal":{"name":"Journal of chromatography. B, Biomedical sciences and applications","volume":"734 1","pages":"23-9"},"PeriodicalIF":0.0000,"publicationDate":"1999-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of chromatography. B, Biomedical sciences and applications","FirstCategoryId":"1085","ListUrlMain":"","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
Abstract
In this paper, a novel HPLC-based method with fluorometric detection of coumarin 7-hydroxylase is presented. The described method provides a time-effective, more sensitive and specific alternative to the previously used spectrofluorometric assay. Using the developed method, metabolism of coumarin in 11 samples of human liver microsomes was evaluated and 1790+/-690 pmol/min/nmol cytochrome P450 (CYP) activity was found. Kinetic parameters and linearity of coumarin 7-hydroxylation were studied in a reconstituted system consisting of recombinant CYP2A6 expressed in Escherichia coli, rat NADPH-CYP reductase and usual components. It was found that a 3.5 to 30 min time of incubation is suitable for estimation of coumarin 7-hydroxylase activity. Observed Km and Vmax values in the CYP2A6 reconstituted system were 1.48+/-0.37 microM and 3360+/-180 pmol product/min/nmol CYP, respectively.