Results 191 to 200 of about 9,789 (207)
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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.
Darlene G. Roberts +4 more
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A rapid radiochemical assay for hypoxanthine-guanine phosphoribosyltransferase
Analytical Biochemistry, 1973Abstract A simple radiochemical method is described for assay of hypoxanthine-guanine phosphoribosyltransferase. 14C-Hypoxanthine is incubated with enzyme PRPP. The labelled product is precipitated on strips of Whatman No. 1 paper by the addition of lanthanum nitrate. Unreacted substrate is eluted with distilled water.
Vincent P. Hollander +1 more
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The Spectrum of Hypoxanthine-Guanine Phosphoribosyltransferase (HPRT) Deficiency
2006Summary The enzyme hypoxanthine-guanine phosphoribo-syltransferase (HPRT) catalyzes the reutilization ofhypoxanthine and guanine to the purine nucleotidesIMP and GMP, respectively. HPRT deficiency is an X-linked disorder characterized by uric acid over-production and variable neurologic impairment.
Rosa J. Torres +5 more
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Levels of hypoxanthine phosphoribosyltransferase RNA in human cells
Experimental Cell Research, 1990The gene for the purine salvage enzyme hypoxanthine phosphoribosyltransferase (HPRT) is expressed at a low level in many cells. As is the case with several other "housekeeping genes," thorough studies of hprt gene regulation have been hampered by the low levels of its mRNA.
Dennis Hellgren +3 more
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Genetic and Clinical Heterogeneity in Hypoxanthine Phosphoribosyltransferase Deficiencies
1995Complete deficiency of HPRT causes the Lesch-Nyhan syndrome (LNS) which is characterized by hyperuricemia, mental retardation, choreoathetosis, and compulsive self-mutilation. Partial deficiency of HPRT leads to a severe form of gout and nephrolithiasis. In contrast to the Lesch-Nyhan syndrome it has been proposed to designate this as Kelley-Seegmiller
Wolf Gutensohn +3 more
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Experimental Cell Research, 1977
Summary Transport of purine bases and nucleosides by a variety of mammalian cell lines is generally accomplished by facilitated diffusion, a non-concentrative, saturable process. However, previous investigators have been unable to detect a saturable component for the transport of hypoxanthine by human fibroblasts deficient in hypoxanthine-guanine ...
Rody P. Cox, M.J. Holland, Ellen Murphy
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Summary Transport of purine bases and nucleosides by a variety of mammalian cell lines is generally accomplished by facilitated diffusion, a non-concentrative, saturable process. However, previous investigators have been unable to detect a saturable component for the transport of hypoxanthine by human fibroblasts deficient in hypoxanthine-guanine ...
Rody P. Cox, M.J. Holland, Ellen Murphy
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1978
Publisher Summary This chapter describes the methodology of hypoxanthine phosphoribosyltransferase and guanine phosphoribosyltransferase enzyme purification from enteric bacteria. Phosphoribosyltransferases (PRTs) for hypoxanthine and guanine are separate activities representing the gene products of only distantly linked genes on the chromosome of ...
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Publisher Summary This chapter describes the methodology of hypoxanthine phosphoribosyltransferase and guanine phosphoribosyltransferase enzyme purification from enteric bacteria. Phosphoribosyltransferases (PRTs) for hypoxanthine and guanine are separate activities representing the gene products of only distantly linked genes on the chromosome of ...
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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 ...
Larry 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
Joseph H. Hersh +5 more
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1974
Partial deficiency of HGPRT, a salvage enzyme of purine metabolism, has been demonstrated to be the primary abnormality causing purine overproduction in a small proportion of patients with gout (1–4). The quantitative deviation in the activity of this enzyme has been shown by Kelley et al.
A. de Vries, Oded Sperling, P. Boer
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Partial deficiency of HGPRT, a salvage enzyme of purine metabolism, has been demonstrated to be the primary abnormality causing purine overproduction in a small proportion of patients with gout (1–4). The quantitative deviation in the activity of this enzyme has been shown by Kelley et al.
A. de Vries, Oded Sperling, P. Boer
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