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A new colorimetric assay for purine nucleoside phosphorylase
Clinical Biochemistry, 1989A new colorimetric procedure for the determination of purine nucleoside phosphorylase (PNP, E.C. 2.4.2.1) activity is described. In this procedure, the hydrogen peroxide formed in the PNP-xanthine oxidase reaction is used to oxidize the chromogenic reagents--3,5-dichloro-2-hydroxybenzenesulfonic acid/4-aminophenazone using the enzyme peroxidase.
Peter Cashion, Samuel Y. Chu, Min Jiang
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Plasma purine nucleoside phosphorylase in cancer patients
Clinica Chimica Acta, 2004Purine nucleoside phosphorylase (PNP) is the purine salvage enzyme that converts guanosine to guanine and inosine to hypoxanthine.279 samples from patients with differing cancers were collected during treatment at both pre- and post-dose stages for plasma PNP activity and compared with a normal population.Normal plasma PNP activity was found to be 3.2+/
Russell P. Newton +2 more
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FISH-MUSCLE PURINE AND PYRIMIDINE NUCLEOSIDE PHOSPHORYLASES
Canadian Journal of Biochemistry, 1967Three purine nucleoside phosphorylase preparations (isoenzymes) were obtained by ammonium sulfate fractionation and DEAE-cellulose chromatography of aqueous extracts of lingcod muscle. Dialysis, adsorption on alumina Cγ, and elution with 0.4 M phosphate buffer yielded further purification.
Joan E. Roy, H. L. A. Tarr
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Genetic Variability of Purine Nucleoside Phosphorylase in the Mouse
1984The inherited human deficiency of purine nucleoside phosphorylase is associated primarily with cellular immune dysfunction1. We have begun to screen for quantitative activity variants of purine nucleoside phosphorylase in Mus musculus in attempts to establish an animal model for the enzyme deficiencies associated with immunodeficiency disease.
Marcia J. Sparling +3 more
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Inhibitors of the enzyme purine nucleoside phosphorylase
Expert Opinion on Therapeutic Patents, 1998The enzyme purine nucleoside phosphorylase (PNP) catalyses the reversible cleavage of purine nucleosides to the purine base and ribose-1-phosphate. Several cases of a rare genetic disorder in which PNP is lacking have been reported in children. These children were found to be T-cell immunodeficient while their B-cell immunity remained normal.
Philip E. Morris, John A. Montgomery
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Chapter 3. Purine Nucleoside Phosphorylase
2007Purine nucleoside phosphorylase (PNP) catalyzes the reversible phosphorolysis of purine ribonucleosides and 2′-deoxypurine ribonucleosides to the free base, and ribose 1-phosphate or 2′-deoxyribose 1-phosphate, respectively.1–3 PNPs are found in most prokaryotic and eukaryotic organisms where the en...
Steven E. Ealick, Yang Zhang
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Purine nucleoside phosphorylase polymorphism in sheep erythrocytes
Biochemical Genetics, 1977A polymorphism of purine nucleoside phosphorylase is described in sheep erythrocytes. Two isozymes were distinguished electrophoretically, one with high activity (NP-1) and one with low activity (NP-2). Breeding data suggest that the two isozymes are the product of two codominant alleles, NP1 and NP2.
P. G. Board, J. E. Smith
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Functional analysis of purine nucleoside phosphorylase as a key enzyme in ribavirin metabolism.
Drug Metabolism and Pharmacokinetics, 2014Ribavirin is a purine nucleoside analogue that possesses potent anti-hepatitis C virus activity, and it has long been considered likely that ribavirin undergoes a first-pass metabolism at the small intestine. Although purine nucleoside phosphorylase (PNP)
Tomomi Furihata +5 more
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Purine Nucleoside Phosphorylase Deficiency: A Mutation Update
Nucleosides, Nucleotides and Nucleic Acids, 2011Purine nucleoside phosphorylase (PNPase) deficiency is an autosomal recessive disorder affecting purine degradation and salvage pathways. Clinically, patients typically present with severe immunodeficiency, neurological dysfunction, and autoimmunity. Biochemically, PNPase deficiency may be suspected in the presence of hypouricemia.
A. Corrigan +5 more
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