titoli, abstracts, parole chiave >>>
Pentose phosphates in nucleoside interconversion and catabolism

Tozzi, Maria Grazia and Camici, Marcella and Mascia, Laura and Sgarrella, Francesco and Ipata, Piero Luigi (2006) Pentose phosphates in nucleoside interconversion and catabolism. FEBS Journal, Vol. 273 (6), p. 1089-1101. eISSN 1742-4658. Article.

Full text not available from this repository.

DOI: 10.1111/j.1742-4658.2006.05155.x


Ribose phosphates are either synthesized through the oxidative branch of the pentose phosphate pathway, or are supplied by nucleoside phosphorylases. The two main pentose phosphates, ribose-5-phosphate and ribose-1-phosphate, are readily interconverted by the action of phosphopentomutase. Ribose-5-phosphate is the direct precursor of 5-phosphoribosyl-1-pyrophosphate, for both de novo and 'salvage' synthesis of nucleotides. Phosphorolysis of deoxyribonucleosides is the main source of deoxyribose phosphates, which are interconvertible, through the action of phosphopentomutase. The pentose moiety of all nucleosides can serve as a carbon and energy source. During the past decade, extensive advances have been made in elucidating the pathways by which the pentose phosphates, arising from nucleoside phosphorolysis, are either recycled, without opening of their furanosidic ring, or catabolized as a carbon and energy source. We review herein the experimental knowledge on the molecular mechanisms by which (a) ribose-1-phosphate, produced by purine nucleoside phosphorylase acting catabolically, is either anabolized for pyrimidine salvage and 5-fluorouracil activation, with uridine phosphorylase acting anabolically, or recycled for nucleoside and base interconversion; (b) the nucleosides can be regarded, both in bacteria and in eukaryotic cells, as carriers of sugars, that are made available though the action of nucleoside phosphorylases. In bacteria, catabolism of nucleosides, when suitable carbon and energy sources are not available, is accomplished by a battery of nucleoside transporters and of inducible catabolic enzymes for purine and pyrimidine nucleosides and for pentose phosphates. In eukaryotic cells, the modulation of pentose phosphate production by nucleoside catabolism seems to be affected by developmental and physiological factors on enzyme levels.

Item Type:Article
ID Code:1342
Uncontrolled Keywords:Deoxyribose-1-phosphate, deoxyribose-5-phosphate, nucleoside interconversion, nucleoside transport, pentose phosphate catabolism, purine nucleoside phosphorylase, pyrimidine salvage, ribose-1-phosphate, ribose-5-phosphate, uridine phosphorylase
Subjects:Area 05 - Scienze biologiche > BIO/10 Biochimica
Divisions:001 Università di Sassari > 01 Dipartimenti > Scienze del farmaco
Publisher:Blackwell / Wiley
Copyright Holders:© 2006 The Authors, Journal compilation © 2006 FEBS
Deposited On:18 Aug 2009 10:04

I documenti depositati in UnissResearch sono protetti dalle leggi che regolano il diritto d'autore

Repository Staff Only: item control page