K. Arora, J. Macleod, John F. Williams
Feb 1, 1987
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0
Influential Citations
6
Citations
Journal
Journal of Labelled Compounds and Radiopharmaceuticals
Abstract
Methods for the enzymic synthesis, isolation, purification and analysis of the 14C labelled intermediates that are characteristic of the L-type pentose phosphate pathway are described. These are D-glycero D-ido octulose 1, 8-bisphosphate and 8-monophosphate; D-glycero D-altro octulose mono- and bisphosphates; sedoheptulose 1,7-bisphosphate and D-arabinose 5-phosphate. The procedures for the preparation of octulose- and sedoheptulose bisphosphates are based on the aldolase-catalyzed condensation of dihydroxyacetone phosphate with appropriately 14C-labelled aldo pentose 5-phosphates and erythrose 4-phosphate respectively. D-Glycero D-ido octulose 8-phosphate and its altro epimer were prepared in transketolase catalyzed reactions involving β-hydroxypyruvate and appropriately 14C-labelled aldohexose 6-phosphates. [U-14C] D-arabinose 5-phosphate was synthesized by reacting [U-14C] glucosamine 6-phosphate with ninhydrin. The authenticity of each of the 14C-labelled sugar phosphates was confirmed using a variety of chromatographic methods, enzymatic analytic methods and NMR spectroscopy. The 14C labelled compounds are used in investigations involving the search for the identity of the pentose pathway in tissues invitro, for the measurement of L-type pathway enzyme reactions and for testing the mechanistic predictions of the L-type pathway in vitro.