Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P00492 (hypoxanthine-guanine phosphoribosyltransferase)
 2,385 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Since organotin compounds represent an environmental health hazard, we determined the effect of triethyltin bromide (TTB) on red blood cell (RBC) enzyme activity. TTB produced a concentration-dependent inhibition of hexokinase and pyrimidine 5'-nucleotidase for both adult and cord RBC. D-Glucose, but not ATP or MgCl2, prevented the hexokinase inhibition by TTB. Glucose-6-phosphate dehydrogenase, adenylate kinase, and hypoxanthine-guanine phosphoribosyltransferase were also inhibited by TTB. Cord RBC enzymes were more resistant to the effects of TTB than were adult RBC enzymes. Although TTB is a potent inhibitor of hexokinase, physiologic concentrations of glucose appear to protect the RBC during clinical tin intoxication.
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PMID:Effect of triethyltin on enzyme activity in human adult and cord red cells. 301 93

GSH, the most abundant erythrocyte thiol, is synthesized from its constituent amino acids by two ATP-dependent enzymes present in the mature red cell. Its unusual gamma-glutamyl linkage precludes degradation by any known red cell peptidase. The erythrocyte lacks a complete "gamma-glutamyl cycle" as described by Meister. GSH has important enzymatic and non-enzymatic roles in oxidoreduction reactions. As the specific co-factor of glutathione peroxidase, it participates in the reduction of harmful organoperoxides. Oxidized glutathione is reconverted to GSH via NADPH-dependent, glutathione reductase. NADPH in the red cell is generated solely by the two dehydrogenases of the pentosephosphate shunt. Increased GSH concentrations are normally present in neonatal erythrocytes. For reasons not clear, they are an epiphenomenon in inherited pyrimidine 5'-nucleotidase deficiency. Many syndromes of heterogeneous etiology having in common dyserythropoietic anemia and ineffective erythropoiesis despite a cellular bone marrow also exhibit abnormally high concentrations of red cell GSH as one component of a constellation of metabolic abnormalities. In a single patient with the Lesch-Nyhan syndrome studied by us, erythrocyte GSH was increased. A kindred with dominantly transmitted (or possibly x-chromosome linked) hereditary hemolytic anemia in which the only thus far detected abnormality is increased red cell GSH has also been documented. The fundamental molecular lesion in this syndrome is unknown.
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PMID:Syndromes with increased red cell glutathione (GSH). 744 Feb 25