title: Discovery of novel human phenylethanolamine N-methyltransferase (hPNMT) inhibitors using 3D pharmacophore-based in silico, biophysical screening and enzymatic activity assays.
abstract: With the aid of receptor-oriented pharmacophore-based in silico screening, we established three pharmacophore maps explaining the binding model of hPNMT and a known inhibitor, SK&F 29661 (Martin et al., 2001). The compound library was searched using these maps. Nineteen selected candidate inhibitors of hPNMT were screened using STD-NMR and fluorescence experiments. An enzymatic activity assay based on HPLC was additionally performed. Consequently, three potential hPNMT inhibitors were identified, specifically, 4-oxo-1,4-dihydroquinoline-3,7-dicarboxylic acid, 4-(benzo[d][1,3]dioxol-5-ylamino)-4-oxobutanoic acid, and 1,4-diaminonaphthalene-2,6-disulfonic acid. These novel inhibitors were retrieved using Map II comprising one hydrogen bond acceptor, one hydrogen bond donor, one lipophilic feature, and shape constraints, including a hydrogen bond between Lys57 of hPNMT and a hydrogen bond donor of the inhibitor, and stacked hydrophobic interactions between the side-chain of Phe182 and an aromatic region of the inhibitor. Water-mediated interactions between Asn267 and Asn39 of hPNMT and the amide or amine group of three potent inhibitors were additional important features for hPNMT activity. The binding model presented here may be applied to identify inhibitors with higher potency. Moreover, our novel compounds are valuable candidates for further lead optimization of PNMT inhibitors.
authors.affiliation: Department of Chemistry, Konkuk University, Seoul, 143-701, Korea.
authors.forename: Dong-Il
authors.initials: DI
authors.lastname: Kang
authors.forename: Jee-Young
authors.initials: JY
authors.lastname: Lee
authors.forename: Woonghee
authors.initials: W
authors.lastname: Kim
authors.forename: Ki-Woong
authors.initials: KW
authors.lastname: Jeong
authors.forename: Soyoung
authors.initials: S
authors.lastname: Shin
authors.forename: Jiyoung
authors.initials: J
authors.lastname: Yang
authors.forename: Eujin
authors.initials: E
authors.lastname: Park
authors.forename: Young Kee
authors.initials: YK
authors.lastname: Chae
authors.forename: Yangmee
authors.initials: Y
authors.lastname: Kim
mesh_terms: D055592:Biophysical Phenomena; D002851:Chromatography, High Pressure Liquid; D020650:Combinatorial Chemistry Techniques; D055808:Drug Discovery / Q000295:instrumentation / Q000379:methods; D004353:Drug Evaluation, Preclinical / Q000295:instrumentation / Q000379:methods; D057075:Enzyme Assays; D004791:Enzyme Inhibitors / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology; D006801:Humans; D006860:Hydrogen Bonding; D008956:Models, Chemical; D008968:Molecular Conformation; D010625:Phenylethanolamine N-Methyltransferase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D011485:Protein Binding
chemical_list: D004791:Enzyme Inhibitors; D010625:Phenylethanolamine N-Methyltransferase