title: Affinity purification and properties of porcine brain aldose reductase.
abstract: Aldose reductase (alditol:NADP+ 1-oxidoreductase, EC 1.1.1.21) has been purified 1500-fold from porcine brain in a four-step procedure employing Blue-Sepharose 6B affinity chromatography. The purified enzyme was shown to be apparently homogeneous by polyacrylamide gel electrophoresis. The enzyme is a single chain polypeptide of molecular weight 40 000, pH optimum 5.0 K(app)(xylose) 4 mM; K(app)(NADPH) 3 microM. The relative substrate activities, activation with sulfate ion, and limited oxidative and NADH-related reductive activities confirm the classification of this enzyme as aldolase reductase. The activity of the reductase with p-nitrobenzaldehyde and 3-indolacetaldehyde and the similarity of its physical properties with the 'low Km' aldehyde reductase of porcine brain previously reported indicates that these enzymes may be identical.
mesh_terms: D000449:Aldehyde Reductase / Q000302:isolation & purification / Q000378:metabolism*; D000818:Animals; D001921:Brain / Q000201:enzymology*; D002846:Chromatography, Affinity; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008970:Molecular Weight; D009249:NADP / Q000494:pharmacology; D013379:Substrate Specificity; D013401:Sugar Alcohol Dehydrogenases / Q000378:metabolism*; D013552:Swine; D014994:Xylose / Q000378:metabolism
chemical_list: D009249:NADP; D014994:Xylose; D013401:Sugar Alcohol Dehydrogenases; D000449:Aldehyde Reductase