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Immunoadsorbent Chromatography of Hypoxanthine-Guanine Phosphoribosyltransferase
1974Recent evidence indicates that the virtual absence of hypoxanthine-guanine phosphoribosyltransferase (HGPRT) in patients with the Lesch-Nyhan syndrome is due in most if not all instances to a mutation(s) on the gene coding for the HGPRT protein (Kelley and Meade, 1971; Rubin, et al., 1971; Arnold, Meade and Kelley, 1972).
W J, Arnold, R B, Jones, W N, Kelley
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The Spectrum of Hypoxanthine-guanine Phosphoribosyltransferase Deficiency
QJM: An International Journal of Medicine, 1973The spectrum of clinical manifestations of hypoxanthine-guanine phosphoribosyltransferase (HGPRTase) deficiency is presented by reference to eight patients from five kindred. These patients illustrate the range of associated neurological findings, together with the variety of presentation and complications due to the associated over-production of urate.
Emmerson, B. T., Thompson, L.
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Hypoxanthine: Guanine phosphoribosyltransferase mutants in Saccharomyces cerevisiae
Molecular and General Genetics MGG, 1983Yeast mutants lacking activity of the enzyme hypoxanthine:guanine phosphoribosyltransferase (H:G-PRT) have been isolated by selecting for resistance to 8-azaguanine in a strain carrying the wild type allele, ade4%, of the gene coding for amidophosphoribosyltransferase (PRPPAT), the first enzyme of de novo purine synthesis.
R A, Woods +4 more
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Hypoxanthine-guanine phosphoribosyltransferase: A simple spectrophotometric assay
Clinica Chimica Acta, 1977A simple spectrophotometric assay is described based on the conversion of hypoxanthine to inosine monophosphate and precipitation of both the reaction product and protein with lanthanum phosphate. The extent of conversion is determined by the fall in absorbance of hypoxanthine at 249 nm.
Johnson L.A., Gordon R.B., Emmerson B.T.
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A spectrophotometric assay for hypoxanthine-guanine phosphoribosyltransferase
Analytical Biochemistry, 1971Abstract The present paper describes a new spectrophotometric assay for HGPRTase activity which is more rapid than and as sensitive as the isotopic assays for this enzyme and which avoids the use of high-voltage electrophoresis and liquid scintillation counting. A simple technique using thin-layer chromatography for the separation of the nucleotide,
D S, Newcombe, J M, Willard
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Transformation of the gene for hypoxanthine phosphoribosyltransferase
Somatic Cell Genetics, 1979Purified DNA from wild-type Chinese ovary (CHO) cells has been used to transform three hypoxanthine phosphoribosyltransferase (HPRT) deficient murine cell mutants to the enzyme positive state. Transformants appeared at an overall frequency of 5 x 10(-8) colonies/treated cell and expressed CHO HPRT activity as determined by electrophoresis.
L H, Graf, G, Urlaub, L A, Chasin
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Hypoxanthine, Guanine, Xanthine Phosphoribosyltransferase Activity inCryptosporidium parvum
Experimental Parasitology, 1998All parasitic protozoa examined to date are incapable of de novo synthesis of purine nucleotides and rely on salvage mechanisms for survival. We have identified hypoxanthine, guanine, xanthine phosphoribosyl-transferase activities in crude cell-free extracts of Cryptosporidium sporulated oocysts utilizing radiolabeled substrates. Guanine, hypoxanthine,
P S, Doyle, J, Kanaani, C C, Wang
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Biochemical Medicine, 1973
Abstract Hypoxanthine transport has been studied in cultured human fibroblasts with normal and mutant H-G PRT. Transport is dependent on cell density, the activity of H-G PRT, and de novo purine synthesis. Transport is decreased in control cultures at high density and in cell strains with a mutant H-G PRT.
P J, Benke, N, Herrick, A, Herbert
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Abstract Hypoxanthine transport has been studied in cultured human fibroblasts with normal and mutant H-G PRT. Transport is dependent on cell density, the activity of H-G PRT, and de novo purine synthesis. Transport is decreased in control cultures at high density and in cell strains with a mutant H-G PRT.
P J, Benke, N, Herrick, A, Herbert
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Genetic Analysis of Human Hypoxanthine-Guanine Phosphoribosyltransferase Deficiency
Enzyme, 1987Hypoxanthine-guanine phosphoribosyltransferase (HPRT; IMP: pyrophosphate phosphoribosyltransferase, EC 2.4.2.8) functions in the purine-metabolic salvage pathway. Two clinical syndromes are associated with a deficiency in HPRT enzyme activity. Virtually complete deficiency leads to the Lesch-Nyhan syndrome, whereas partial deficiency results in ...
L J, Silverman +2 more
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Clinical correlations in partial hypoxanthine guanine phosphoribosyltransferase deficiency
Pediatric Neurology, 1986Erythrocyte assays for hypoxanthine guanine phosphoribosyltransferase (HGPRT) activity performed on two male half-siblings with hyperuricemia, produced results consistent with classic Lesch-Nyhan syndrome. Due to the absence of neurologic abnormalities, cognitive deficits, or self-mutilation, HGPRT activity was measured by intact fibroblast assay which
J H, Hersh +5 more
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