STRUCTURE OF PORCINE ALDEHYDE REDUCTASE HOLOENZYME

Aldehyde reductase, a member of the aldo-keto reductase superfamily, c atalyzes the NADPH-dependent reduction of a variety of aldehydes to th eir corresponding alcohols. The structure of porcine aldehyde reductas e-NADPH binary complex has been determined by X-ray diffraction method s and refined to a crystallographic R-factor of 0.20 at 2.4 Angstrom r esolution. The tertiary structure of aldehyde reductase is similar to that of aldose reductase and consists of an alpha/beta-barrel with the active site located at the carboxy terminus of the strands of the bar rel, Unlike aldose reductase, the N epsilon 2 of the imidazole ring of His 113 in aldehyde reductase interacts, through a hydrogen bond, wit h the amide group of the nicotinamide ring of NADPH.