title: Human cytochrome P450 4F11: heterologous expression in bacteria, purification, and characterization of catalytic function.
abstract: Human cytochrome P450 (P450) 4F11 is still considered an "orphan" because its function is not well characterized. A bacterial expression system was developed for human P450 4F11, producing approximately 230nmol P450 from a 3-l culture of Escherichia coli. P450 4F11 was purified and utilized for untargeted substrate searches in human liver extract using a liquid chromatography/mass spectrometry-based metabolomic and isotopic labeling approach (Tang et al., 2009 [19]). Four fatty acids-palmitic, oleic, arachidonic, and docosahexaenoic-were identified in human liver and verified as substrates of P450 4F11. The products were characterized as omega-hydroxylated fatty acids by gas chromatography-mass spectrometry analysis of their trimethylsilyl derivatives. Kinetic analysis of the oxidation products confirmed that the fatty acids are substrates oxidized by P450 4F11. P450 4F11 also exhibited low activity for some drug N-demethylation reactions but none for activation of several pro-carcinogens.
authors.affiliation: Department of Biochemistry and Center in Molecular Toxicology, Vanderbilt University School of Medicine, Nashville, TN 37232-0146, USA.
authors.forename: Zhongmei
authors.initials: Z
authors.lastname: Tang
authors.forename: Sandra Giovanna
authors.initials: SG
authors.lastname: Salamanca-Pinzón
authors.forename: Zhong-Liu
authors.initials: ZL
authors.lastname: Wu
authors.forename: Yi
authors.initials: Y
authors.lastname: Xiao
authors.forename: F Peter
authors.initials: FP
authors.lastname: Guengerich
mesh_terms: D000595:Amino Acid Sequence; D055162:Biocatalysis; D001711:Biotransformation; D002273:Carcinogens / Q000493:pharmacokinetics; D002846:Chromatography, Affinity; D003577:Cytochrome P-450 Enzyme System / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D000072470:Cytochrome P450 Family 4; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000235:genetics*; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D007700:Kinetics; D008099:Liver / Q000201:enzymology; D008969:Molecular Sequence Data; D013056:Spectrophotometry, Ultraviolet; D013379:Substrate Specificity; D053719:Tandem Mass Spectrometry
chemical_list: D002273:Carcinogens; D003577:Cytochrome P-450 Enzyme System; D000072470:Cytochrome P450 Family 4; C492722:CYP4F11 protein, human