title: Inhibition of Recombinant Aldose-6-Phosphate Reductase from Peach Leaves by Hexose-Phosphates, Inorganic Phosphate and Oxidants.
abstract: Glucitol, also known as sorbitol, is a major photosynthetic product in plants from the Rosaceae family. This sugar alcohol is synthesized from glucose-6-phosphate by the combined activities of aldose-6-phosphate reductase (Ald6PRase) and glucitol-6-phosphatase. In this work we show the purification and characterization of recombinant Ald6PRase from peach leaves. The recombinant enzyme was inhibited by glucose-1-phosphate, fructose-6-phosphate, fructose-1,6-bisphosphate and orthophosphate. Oxidizing agents irreversibly inhibited the enzyme and produced protein precipitation. Enzyme thiolation with oxidized glutathione protected the enzyme from insolubilization caused by diamide, while incubation with NADP+ (one of the substrates) completely prevented enzyme precipitation. Our results suggest that Ald6PRase is finely regulated to control carbon partitioning in peach leaves.
authors.affiliation: Instituto de Agrobiotecnología del Litoral, UNL, CONICET, FBCB, Colectora Ruta Nacional, Santa Fe, Argentina.
authors.forename: Matías D
authors.initials: MD
authors.lastname: Hartman
authors.affiliation: Instituto de Agrobiotecnología del Litoral, UNL, CONICET, FBCB, Colectora Ruta Nacional, Santa Fe, Argentina.
authors.forename: Carlos M
authors.initials: CM
authors.lastname: Figueroa
authors.affiliation: Instituto de Agrobiotecnología del Litoral, UNL, CONICET, FBCB, Colectora Ruta Nacional, Santa Fe, Argentina.
authors.forename: Diego G
authors.initials: DG
authors.lastname: Arias
authors.affiliation: Instituto de Agrobiotecnología del Litoral, UNL, CONICET, FBCB, Colectora Ruta Nacional, Santa Fe, Argentina.
authors.forename: Alberto A
authors.initials: AA
authors.lastname: Iglesias
mesh_terms: D000449:Aldehyde Reductase / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D005635:Fructosediphosphates / Q000378:metabolism / Q000494:pharmacology; D005636:Fructosephosphates / Q000378:metabolism / Q000494:pharmacology; D005958:Glucosephosphates / Q000378:metabolism / Q000494:pharmacology; D019803:Glutathione Disulfide / Q000378:metabolism; D006600:Hexosephosphates / Q000378:metabolism / Q000494:pharmacology; D015151:Immunoblotting; D007700:Kinetics; D008954:Models, Biological; D009249:NADP / Q000378:metabolism; D016877:Oxidants / Q000378:metabolism / Q000494:pharmacology; D010710:Phosphates / Q000378:metabolism / Q000494:pharmacology; D010802:Phylogeny; D018515:Plant Leaves / Q000201:enzymology* / Q000235:genetics; D010940:Plant Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D000068242:Prunus domestica / Q000201:enzymology* / Q000235:genetics; D011994:Recombinant Proteins / Q000378:metabolism; D013379:Substrate Specificity; D013438:Sulfhydryl Compounds / Q000378:metabolism
chemical_list: D005635:Fructosediphosphates; D005636:Fructosephosphates; D005958:Glucosephosphates; D006600:Hexosephosphates; D016877:Oxidants; D010710:Phosphates; D010940:Plant Proteins; D011994:Recombinant Proteins; D013438:Sulfhydryl Compounds; D009249:NADP; C027618:fructose-6-phosphate; C031590:glucose-1-phosphate; D000449:Aldehyde Reductase; C029063:fructose-1,6-diphosphate; D019803:Glutathione Disulfide
keywords: Carbon partitioning; Glucitol; Peach; Prunus persica; Redox regulation; Sorbitol