Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.5 (5'-nucleotidase)
 3,167 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Enzymopathies are described concerning the enzymes of the oxidative pentose phosphate pathway including the glutathion system, of the majority of glycolytic enzymes as well as of the ATPase, adenylate kinase and pyrimidine-5'-nucleotidase. The distribution and the frequency of the enzymopathies differ strongly in the various regions of the world. Glucose-6-phosphate dehydrogenase and pyruvate kinase show the highest frequency. The detected polymorphism of the pathological enzyme variants is one of the reasons for the fact that no correlation between the decrease of the catalytic activity and the severity of the anaemias has been found. For the identification of risk-groups more precise methods are necessary. Till now the detailed relationships between enzymopathy and non-spherocytic haemolytic anaemias are not clarified. Furthermore the molecular mechanism of the instability of pathological enzyme variants is not yet clear.
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PMID:[Enzyme deficient non-spherocytic hemolytic anemias]. 67 10

We evaluated the erythrocytes of two patients with hereditary pyrimidine 5'-nucleotidase deficiency. Significant findings included an increased reduced glutathione content, increased incubated Heinz body formation, a positive ascorbate cyanide test, and decreased intraerythrocytic pH. The pentose phosphate shunt activity of the patients' red cells as measured by the release of 14CO2 from 14C-1-glucose was decreased compared to high reticulocyte controls. Glucose-6-phosphate dehydrogenase (G6PD) activity in hemolysates from control erythrocytes was inhibited 43% by 5.5 mM cytidine 5'-triphosphate (CTP) and 50% by 5.5 mM in uridine 5'-triphosphate (UTP) at pH 7.1. CTP was a competitive inhibitor for G6P (Ki = 1.7 mM) and a noncompetitive inhibitor for NADP+ (Ki = 7.8 mM). Glutathione peroxidase, glutathione reductase, and 6-phosphogluconate dehydrogenase were not affected by these compounds. Pentose phosphate shunt activity in control red cell hemolysate at pH 7.1 was inhibited to a similar degree by 5.5 mM CTP or UTP. Since the intracellular concentrations of G6P and NADP+ are below their KmS for G6PD, these data suggest that high concentrations of pyrimidine 5'-nucleotides depress pentose phosphate shunt activity in pyrimidin 5'-nucleotidase deficiency. Thus, this impairment of the pentose phosphate pathway appears to contribute to the pathogenesis of hemolysis in pyrimidine 5'-nucleotidase deficiency hemolytic anemia.
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PMID:Hemolytic anemia in hereditary pyrimidine 5'-nucleotidase deficiency: nucleotide inhibition of G6PD and the pentose phosphate shunt. 628 44