Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002878 (hemolytic anemia)
 7,530 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A new mutant red cell PK associated with mild chronic haemolytic anaemia is described. The propositus, double heterozygous for a maternal gene coding for a structural abnormal enzyme and a paternal gene coding for a catalitically inactive enzyme, was suitable for an accurate functional characterization of the PK variant since his erythrocytes contained only one active mutant form of this enzyme. The active isoenzyme was characterized by low activity, decreased affinity for phosphoenolpyruvate, incomplete fructose-1,6-diphosphate activation, increased 'zero-time transition temperature', increased stability to guanidine-HCl and storage at +4 degrees C, increased guanosine-5'-diphosphate and cytidine-5'-diphosphate utilization, altered electrophoretic pattern with a single slow-moving component and abnormal isoelectric point. Affinity for ADP, ATP inhibition, optimum pH, molecular weight of the subunits, antigen concentration and immunological properties were in the normal range.
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PMID:Concomitance of an active and an inactive mutant of red cell pyruvate kinase (PK). 43 51

We evaluated the glycolytic intermediate concentrations from the erythrocytes of a patient with hereditary pyrimidine 5'-nucleotidase (P5'N) deficiency. Conclusive evidence for a metabolic block was not found. We evaluated the effects of the pyrimidine (cytidine and uridine) tri- and diphosphate nucleotides (CTP, CDP, UTP, UDP) and the choline and ethanolamine derivatives of CDP (CDP-choline, CDP-ethanolamine) on the activities of key enzymes of the Embden-Meyerhof pathway. CTP and UTP inhibited fructose-6-phosphate competitively for phosphofructokinase and phosphoenolpyruvate competitively for pyruvate kinase. In both cases, the Ki of the pyrimidine nucleotide and Km of the glycolytic substrate were above their intraerythrocytic concentrations. CTP was a competitive inhibitor of ADP for pyruvate kinase with a Ki near its intraerythrocytic concentration. CDP-choline and CDP-ethanolamine had no effect on the activities of Embden-Meyerhof or pentose phosphate shunt enzymes. Thus, the nature of the hemolytic anemia in hereditary P5'N deficiency remains enigmatic.
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PMID:Hemolytic anemia in hereditary pyrimidine 5'-nucleotidase deficiency. II. Effect of pyrimidine nucleotides and their derivatives on glycolytic and pentose phosphate shunt enzyme activity. 609 51

The concentrations of red cell CDP (dCDP)-choline and P-choline were measured and compared in normal subjects, in subjects with hemolytic anemia other than that due to pyrimidine-5'-nucleotidase deficiency, in homozygotes for the latter enzymopathy, and in a single subject with a hemolytic syndrome speculatively due to choline phosphotransferase deficiency.
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PMID:Red cell CDP (dCDP)-choline and P-choline in normal subjects and in certain hemolytic syndromes. 633 Nov 56

Erythrocytes from a young woman with chronic hemolytic anemia were found to contain 0.31-0.45 mM CDP-choline, concentrations that are 15-25 times those in normal erythrocytes and equivalent to 20-30% of the total adenine nucleotide content. Accumulation of CDP-choline has been reported only in erythrocytes from subjects with severe (homozygous) pyrimidine nucleotidase deficiency. In the latter syndrome, however, pyrimidine nucleotidase activity is very low and a spectrum of uridine- and cytidine-containing nucleotides is present along with epiphenomena involving glutathione and ribosephosphate pyrophosphokinase. By contrast, selective accumulation of CDP-choline was the only abnormality demonstrable in proband erythrocytes. Membrane phospholipids were quantitatively and qualitatively normal, compatible with the observation that mature erythrocytes maintain membrane phospholipids largely by passive exchange with plasma components or by acylation of lysophospholipids. Although the presence of small amounts of other CDP-containing cofactors, such as CDP-ethanolamine, could not be entirely excluded, the cytidine/choline ratio closely approximated 1:1 in all studies. These data are compatible with the view that choline phosphotransferase and ethanolamine phosphotransferase are separate enzymes in erythroid cells. Selective accumulation of CDP-choline in proband erythrocytes is also compatible with an inherited deficiency of choline phosphotransferase in erythroid precursors, though this hypothesis remains unproved.
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PMID:Selective accumulation of cytosol CDP-choline as an isolated erythrocyte defect in chronic hemolysis. 657 71

Cysteinyl residues of red cell pyruvate kinase (PK; ATP: pyruvate phosphotransferase, EC 2.7.1.40) were modified with methylmethanethiosulfonate (MMTS), p-nitrophenoxycarbonyl methyl disulfide (NPCMD), and sodium tetrathionate (NaTT). At pH greater than 7 . 0, K0.5 s phosphoenol-pyruvate (PEP) was markedly increased. Fructose-1,6-diphosphate (FDP) increased affinity for PEP, but K0.5 s (PEP) remained elevated and hyperbolic kinetics were not achieved. Inhibition by negative effectors ATP and alanine was not reversed by PEP and FDP concentrations far greater than those abolishing inhibition of unmodified enzyme. At pH less than 7 . 0, PEP affinity was reduced, and FDP markedly increased Vmax and diminished K0.5 s (PEP). MMTS greatly impaired the thermostability of PK. Acid pH alone and the simultaneous presence of Mg++, K+ and PEP prior to MMTS treatment protected against the effects on PEP kinetics, but did not alter the induction of thermolability. No MMTS effect on the FDP binding site, on ADP kinetics or on the relative effectiveness of GDP, UDP or CDP cofactors was demonstrated. The MMTS-induced alterations closely resembled those observed with certain PK mutants associated with haemolytic anaemia.
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PMID:Studies with human erythrocyte pyruvate kinase (PK): effects of modification of sulfhydryl groups. 682 84