title: Crystal structure of meso-2,3-butanediol dehydrogenase in a complex with NAD+ and inhibitor mercaptoethanol at 1.7 A resolution for understanding of chiral substrate recognition mechanisms.
abstract: The crystal structure of a ternary complex of meso-2,3-butanediol dehydrogenase with NAD+ and a competitive inhibitor, mercaptoethanol, has been determined at 1.7 A resolution by means of molecular replacement and refined to a final R-factor of 0.194. The overall structure is similar to those of the other short chain dehydrogenase/reductase enzymes. The NAD+ binding site, and the positions of catalytic residues Ser139, Tyr152, and Lys156 are also conserved. The crystal structure revealed that mercaptoethanol bound specifically to meso-2,3-butanediol dehydrogenase. Two residues around the active site, Gln140 and Gly183, forming hydrogen bonds with the inhibitor, are important but not sufficient for distinguishing stereoisomerism of a chiral substrate.
authors.affiliation: Institute for Protein Research, Osaka University, Suita, Osaka 565-0871, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Otagiri
authors.forename: G
authors.initials: G
authors.lastname: Kurisu
authors.forename: S
authors.initials: S
authors.lastname: Ui
authors.forename: Y
authors.initials: Y
authors.lastname: Takusagawa
authors.forename: M
authors.initials: M
authors.lastname: Ohkuma
authors.forename: T
authors.initials: T
authors.lastname: Kudo
authors.forename: M
authors.initials: M
authors.lastname: Kusunoki
mesh_terms: D000429:Alcohol Oxidoreductases / Q000737:chemistry* / Q000378:metabolism; D003460:Crystallization; D066298:In Vitro Techniques; D007711:Klebsiella pneumoniae / Q000201:enzymology; D008623:Mercaptoethanol / Q000037:antagonists & inhibitors / Q000737:chemistry*; D009243:NAD / Q000737:chemistry* / Q000378:metabolism; D013237:Stereoisomerism; D013379:Substrate Specificity
chemical_list: D009243:NAD; D008623:Mercaptoethanol; D000429:Alcohol Oxidoreductases; C060833:butanol dehydrogenase