title: Bioconversion of deoxypodophyllotoxin into epipodophyllotoxin in E. coli using human cytochrome P450 3A4.
abstract: Biotransformation of deoxypodophyllotoxin to epipodophyllotoxin by three major human hepatic enzymes, CYP1A2, CYP2C9 and CYP3A4, heterologously expressed in E. coli DH5alpha, was investigated. It was shown that CYP3A4 catalysed the hydroxylation of deoxypodophyllotoxin into epipodophyllotoxin in yields up to 90%. The structure of the metabolite was determined using HPLC-MS and HPLC-SPE-NMR techniques. There was no detectable production of epipodophyllotoxin or podophyllotoxin by CYP1A2 and CYP2C9 enzymes. The CYP3A4 enzyme shows a distinctly different reactivity to deoxypodophyllotoxin compared to the semi-synthetic derivatives etoposide and teniposide, which are degraded by 3-O-demethylation. These findings demonstrate a novel system for the production of 2,7'-cyclolignans, starting from the easily accessible deoxypodophyllotoxin.
authors.affiliation: Department of Pharmaceutical Biology, University of Groningen, Groningen Research Institute of Pharmacy (GRIP), Antonius Deusinglaan 1, NL-9713 AV Groningen, The Netherlands.
authors.forename: Nikolay P
authors.initials: NP
authors.lastname: Vasilev
authors.forename: Mattijs K
authors.initials: MK
authors.lastname: Julsing
authors.forename: Albert
authors.initials: A
authors.lastname: Koulman
authors.forename: Cailean
authors.initials: C
authors.lastname: Clarkson
authors.forename: Herman J
authors.initials: HJ
authors.lastname: Woerdenbag
authors.forename: Iliana
authors.initials: I
authors.lastname: Ionkova
authors.forename: Rein
authors.initials: R
authors.lastname: Bos
authors.forename: Jerzy W
authors.initials: JW
authors.lastname: Jaroszewski
authors.forename: Oliver
authors.initials: O
authors.lastname: Kayser
authors.forename: Wim J
authors.initials: WJ
authors.lastname: Quax
mesh_terms: D001711:Biotransformation; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics / Q000378:metabolism*; D004365:Drugs, Chinese Herbal; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D024861:Genetic Enhancement / Q000379:methods; D006801:Humans; D011034:Podophyllotoxin / Q000031:analogs & derivatives* / Q000378:metabolism*; D015202:Protein Engineering / Q000379:methods*; D011994:Recombinant Proteins / Q000378:metabolism
chemical_list: D004365:Drugs, Chinese Herbal; D011994:Recombinant Proteins; C014451:deoxypodophyllotoxin; D003577:Cytochrome P-450 Enzyme System; D011034:Podophyllotoxin