title: L-Idose: an attractive substrate alternative to D-glucose for measuring aldose reductase activity.
abstract: Although glucose is one of the most important physio-pathological substrates of aldose reductase, it is not an easy molecule for in vitro investigation into the enzyme. In many cases alternative aldoses have been used for kinetic characterization and inhibition studies. However these molecules do not completely match the structural features of glucose, thus possibly leading to results that are not fully applicable to glucose. We show how aldose reductase is able to act efficiently on L-idose, the C-5 epimer of D-glucose. This is verified using both the bovine lens and the human recombinant enzymes. While the kcat values obtained are essentially identical to those measured for D-glucose, a significant decrease in KM was observed. This can be due to the significantly higher level of the free aldehyde form present in L-idose compared to D-glucose. We believe that L-idose is the best alternative to D-glucose in studies on aldose reductase.
authors.affiliation: University of Pisa, Department of Biology, Biochemistry Unit, via S. Zeno, 51, Pisa 56127, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Balestri
authors.affiliation: University of Pisa, Department of Biology, Biochemistry Unit, via S. Zeno, 51, Pisa 56127, Italy.
authors.forename: Mario
authors.initials: M
authors.lastname: Cappiello
authors.affiliation: University of Pisa, Department of Biology, Biochemistry Unit, via S. Zeno, 51, Pisa 56127, Italy.
authors.forename: Roberta
authors.initials: R
authors.lastname: Moschini
authors.affiliation: University of Pisa, Department of Biology, Biochemistry Unit, via S. Zeno, 51, Pisa 56127, Italy.
authors.forename: Rossella
authors.initials: R
authors.lastname: Rotondo
authors.affiliation: University of Pisa, Department of Biology, Biochemistry Unit, via S. Zeno, 51, Pisa 56127, Italy.
authors.forename: Irene
authors.initials: I
authors.lastname: Buggiani
authors.affiliation: University of Pisa, Department of Biology, Biochemistry Unit, via S. Zeno, 51, Pisa 56127, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Pelosi
authors.affiliation: University of Pisa, Department of Biology, Biochemistry Unit, via S. Zeno, 51, Pisa 56127, Italy.
authors.forename: Umberto
authors.initials: U
authors.lastname: Mura
authors.affiliation: University of Pisa, Department of Biology, Biochemistry Unit, via S. Zeno, 51, Pisa 56127, Italy. Electronic address: antonella.delcorso@unipi.it.
authors.forename: Antonella
authors.initials: A
authors.lastname: Del-Corso
mesh_terms: D000449:Aldehyde Reductase / Q000378:metabolism*; D000818:Animals; D055162:Biocatalysis / Q000187:drug effects; D002417:Cattle; D005947:Glucose / Q000378:metabolism*; D006601:Hexoses / Q000378:metabolism*; D006801:Humans; D048289:Imidazolidines / Q000494:pharmacology; D007700:Kinetics; D010084:Oxidation-Reduction / Q000187:drug effects; D013379:Substrate Specificity / Q000187:drug effects
chemical_list: D006601:Hexoses; D048289:Imidazolidines; C010997:idose; D000449:Aldehyde Reductase; C026411:sorbinil; D005947:Glucose
keywords: Aldose reductase; d-glucose; l-idose