title: Rapid methods for the high yield synthesis of carbon-13 enriched intermediates of the pentose-phosphate pathway.
abstract: Methods for the synthesis of carbon-13 enriched substrates, intermediates and products of the pentose-phosphate pathway, viz. ribose, arabinose, xylulose and ribulose 5-phosphates, sedoheptulose mono- and bisphosphates, octulose (both the ido- and altro-epimers) mono- and bisphosphates, are described. The procedure of the classical Kiliani synthesis was adopted for the preparation of the two starting compounds, [1-13C]ribose and [1-13C]arabinose 5-phosphates. Using these initial reactants and enzymic methods involving the group-transferring enzymes, transketolase, aldolase and transaldolase, a variety of specifically 13C-labelled five-, six-, seven- and eight-carbon sugar phosphates were synthesized in high yield and purity. The isolation and authenticity of each of the 13C-labelled sugars were established by column, paper and thin layer chromatographic methods and specific enzymic assays. The purity and positional isotopic analysis of these sugar-P's were confirmed by 13C-NMR spectroscopy. These specifically 13C-enriched compounds are required for enzymatic, mechanistic and quantitative investigations of pentose-pathway reactions in animal, plant and tumour tissues in vitro and in vivo.
authors.affiliation: Department of Biochemistry, Australian National University, Canberra, ACT.
authors.forename: K K
authors.initials: KK
authors.lastname: Arora
authors.forename: J G
authors.initials: JG
authors.lastname: Collins
authors.forename: J K
authors.initials: JK
authors.lastname: MacLeod
authors.forename: J F
authors.initials: JF
authors.lastname: Williams
mesh_terms: D002247:Carbon Isotopes; D004798:Enzymes / Q000378:metabolism; D007202:Indicators and Reagents; D007553:Isotope Labeling / Q000379:methods; D010427:Pentose Phosphate Pathway; D013403:Sugar Phosphates / Q000138:chemical synthesis*
chemical_list: D002247:Carbon Isotopes; D004798:Enzymes; D007202:Indicators and Reagents; D013403:Sugar Phosphates