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Mutations in purine nucleoside phosphorylase deficiency
Human Mutation, 1997Purine nucleoside phosphorylase deficiency is an inherited disease of purine metabolism characterized clinically as combined immunodeficiency. The molecular defects have been published for 4 different alleles in 3 patients. We report four new mutations including two amino acid substitutions, A174P and G190V, a single codon deletion, delta I129, and a ...
M L, Markert +8 more
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Purine Nucleoside Phosphorylase. 2. Catalytic Mechanism
Biochemistry, 1997X-ray crystallography, molecular modeling, and site-directed mutagenesis were used to delineate the catalytic mechanism of purine nucleoside phosphorylase (PNP). PNP catalyzes the reversible phosphorolysis of purine nucleosides to the corresponding purine base and ribose 1-phosphate using a substrate-assisted catalytic mechanism.
M D, Erion +4 more
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Inherited variants of human nucleoside phosphorylase
Annals of Human Genetics, 1971SUMMARY1. A method, for the starch gel electrophoresis of human nucleoside phosphorylase (NP) is described. Multiple NP isozymes were found in most human tissues and the best resolution of these isozymes was achieved by electrophoresis in a buffer system containing lithium ions.2.
Y H, Edwards, D A, Hopkinson, H, Harris
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Purine nucleoside phosphorylase from bovine liver
Comparative Biochemistry and Physiology Part B: Comparative Biochemistry, 19781. Purine nucleoside phosphorylase (purine nucleoside:orthophosphate ribosyltransferase, E.C. 2.4.2.1) from liver of cattle, Bos taurus, was purified to homogeneity. Some properties of the enzymes from three different bovine tissues were compared and discussed. 2.
Z, Ikezawa +3 more
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Allosteric regulation of purine nucleoside phosphorylase
Archives of Biochemistry and Biophysics, 1991Purine nucleoside phosphorylase (EC 2.4.2.1) from bovine spleen is allosterically regulated. With the substrate inosine the enzyme displayed complex kinetics: positive cooperativity vs inosine when this substrate was close to physiological concentrations, negative cooperativity at inosine concentrations greater than 60 microM, and substrate inhibition ...
P A, Ropp, T W, Traut
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Stroke in purine nucleoside phosphorylase deficiency
Pediatric Neurology, 1995The first documented case of cerebrovascular disease occurring in a 13-year-old girl with purine nucleoside phosphorylase deficiency is reported. This patient, the oldest known survivor with purine nucleoside phosphorylase deficiency, had previously experienced multiple sequential neurologic problems.
D A, Tam, R T, Leshner
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Inhibition of Intestinal Pyrimidine Nucleoside Phosphorylases
Pharmaceutical Research, 1987The activity of 5'-deoxy-5-fluorouridine (dFUR) depends on its activation to 5-fluorouracil (FU) by pyrimidine nucleoside phosphorylases. These enzymes are found in tumors and normal tissues, with the highest activity in the small intestines. The present study examined the inhibition of dFUR phosphorolysis in intestinal tissues.
M G, Wientjes, J L, Au
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Prenatal exclusion of purine nucleoside phosphorylase deficiency
European Journal of Pediatrics, 1986We report on the prenatal exclusion of purine nucleoside phosphorylase (PNP) deficiency in a fetus whose parents were known to be heterozygotes for the enzyme defect. Prenatal investigation was performed in the 16th week of gestation on amniotic fluid and cultured amnion cells using sensitive techniques.
E. Carapella De Luca +6 more
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16 Purine Nucleoside Phosphorylase
1972Publisher Summary This chapter focuses on purine nucleoside phosphorylases (PNPases), which are widely distributed in nature and have been identified and studied in a number of tissues in mammals, chickens, fish, yeast, and in several species of bacteria. In the erythrocytes of dogs, the activity of PNPase is remarkably low when compared with the red
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