Purification and properties of pyruvate kinase in normal and in pyruvate kinase deficient human red blood cells
1971; Elsevier BV; Volume: 227; Issue: 2 Linguagem: Inglês
10.1016/0005-2744(71)90068-4
ISSN1878-1454
AutoresKarl G. Blume, Radegund Hoffbauer, D. Büsch, H. Arnold, G. W. Löhr,
Tópico(s)Metabolism, Diabetes, and Cancer
Resumo1. Pyruvate kinase (ATP-pyruvate phosphotransferase, EC 2.7.1.40) from normal and enzyme-dificient human red blood cells was purified 10 000-fold with an overall yield of 10%. 2. The molecular weight of the different variants of pyruvate kinase was determined by dextran gel filtration by Sephadex G-200 and was found to be 195 000 ± 6000. 3. In high-voltage electrophoresis the pattern of normal red blood cell pyruvate kinase shows three fractions, two being interconvertible. In enzyme-different material one of the three fractions was not detectable because of its pronounced instability. 4. A Stepwise purification of the three electrophoretic fractions can be achieved by (NH4)2SO4 precipitation. The kinetic constants of the fractions from all phenotypes do not differ significantly with respect to ADP and phosphoenolpyruvate.A striking difference was found in enzymic activation by the allosteric effector fructose 1,6-diphosphate.
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