title: Structure of aldehyde reductase in ternary complex with a 5-arylidene-2,4-thiazolidinedione aldose reductase inhibitor.
abstract: The structure of aldehyde reductase (ALR1) in ternary complex with the coenzyme NADPH and [5-(3-carboxymethoxy-4-methoxybenzylidene)-2,4-dioxothiazolidin-3-yl]acetic acid (CMD), a potent inhibitor of aldose reductase (ALR2), was determined at 1.99A resolution. The partially disordered inhibitor formed a tight network of hydrogen bonds with the active site residues (Tyr50 and His113) and coenzyme. Molecular modelling calculations and inhibitory activity measurements of CMD and [5-(3-hydroxy-4-methoxybenzylidene)-2,4-dioxothiazolidin-3-yl]acetic acid (HMD) indicated that pi-stacking interactions with several conserved active site tryptophan residues and hydrogen-bonding interactions with the non-conserved C-terminal residue Leu300 in ALR2 (Pro301 in ALR1) contributed to inhibitor selectivity. In particular for the potent inhibitor CMD, the rotameric state of the conserved residue Trp219 (Trp220 in ALR1) is important in forming a pi-stacking interaction with the inhibitor in ALR2 and contributes to the difference in the binding of the inhibitor to the enzymes.
authors.affiliation: Medicinal Chemistry and Drug Action, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Carbone
authors.forename: Marco
authors.initials: M
authors.lastname: Giglio
authors.forename: Roland
authors.initials: R
authors.lastname: Chung
authors.forename: Trevor
authors.initials: T
authors.lastname: Huyton
authors.forename: Julian
authors.initials: J
authors.lastname: Adams
authors.forename: Rosanna
authors.initials: R
authors.lastname: Maccari
authors.forename: Rosaria
authors.initials: R
authors.lastname: Ottana
authors.forename: Akira
authors.initials: A
authors.lastname: Hara
authors.forename: Ossama
authors.initials: O
authors.lastname: El-Kabbani
mesh_terms: D000449:Aldehyde Reductase / Q000037:antagonists & inhibitors* / Q000737:chemistry; D020134:Catalytic Domain; D018360:Crystallography, X-Ray; D004791:Enzyme Inhibitors / Q000737:chemistry*; D006860:Hydrogen Bonding; D020128:Inhibitory Concentration 50; D008958:Models, Molecular; D015394:Molecular Structure; D045162:Thiazolidinediones / Q000737:chemistry
chemical_list: D004791:Enzyme Inhibitors; D045162:Thiazolidinediones; D000449:Aldehyde Reductase