title: Preparation, characterization, and substrate metabolism of gold-immobilized cytochrome P450 2C9.
abstract: The cytochrome P450 enzymes represent an important class of heme-containing enzymes. There is considerable interest in immobilizing these enzymes on a surface so that interactions between a single enzyme and other species can be studied with respect to electron transfer, homodimer or heterodimer interactions, or for construction of biological-based chips for standardizing cytochrome P450 metabolism or for high-throughput screening of pharmaceutical agents. Previous studies have generally immobilized P450 enzymes in a matrix or on a surface. Here, we have attached CYP2C9 to gold substrates such that the resulting construct maintains the ability to bind and metabolize substrates in the presence of NADPH and cytochrome P450 reductase. The activity of these chips is directly dependent upon the linkers used to attach CYP2C9 and to the presence of key molecules in the active site during enzyme attachment. A novel method to detect substrate-enzyme binding, namely, superconducting quantum interference device (SQUID) magnetometry, was used to monitor the binding of substrates. Most significantly, conditions that allow measurable CYP2C9 metabolism to occur have been developed.
authors.affiliation: Basic Pharmaceutical Sciences, West Virginia University, P.O. Box 9530, Morgantown, WV 26506, USA. pgannett@hsc.wvu.edu
authors.forename: Peter M
authors.initials: PM
authors.lastname: Gannett
authors.forename: Jarod
authors.initials: J
authors.lastname: Kabulski
authors.forename: Felio A
authors.initials: FA
authors.lastname: Perez
authors.forename: Zhongyuan
authors.initials: Z
authors.lastname: Liu
authors.forename: David
authors.initials: D
authors.lastname: Lederman
authors.forename: Charles W
authors.initials: CW
authors.lastname: Locuson
authors.forename: Robyn R
authors.initials: RR
authors.lastname: Ayscue
authors.forename: Nissa M
authors.initials: NM
authors.lastname: Thomsen
authors.forename: Timothy S
authors.initials: TS
authors.lastname: Tracy
mesh_terms: D001189:Aryl Hydrocarbon Hydroxylases / Q000737:chemistry* / Q000378:metabolism*; D001665:Binding Sites; D065729:Cytochrome P-450 CYP2C9; D006046:Gold / Q000737:chemistry* / Q000378:metabolism*; D006801:Humans; D009249:NADP / Q000737:chemistry / Q000378:metabolism; D009251:NADPH-Ferrihemoprotein Reductase / Q000737:chemistry / Q000378:metabolism; D011487:Protein Conformation; D017434:Protein Structure, Tertiary
chemical_list: D009249:NADP; D006046:Gold; C450260:CYP2C9 protein, human; D065729:Cytochrome P-450 CYP2C9; D001189:Aryl Hydrocarbon Hydroxylases; D009251:NADPH-Ferrihemoprotein Reductase