A comparative kinetics and regulatory study of pyruvate kinase from rat erythrocytes, reticulocytes and bone marrow...

The kinetics of pyruvate kinase (PK) at various phosphoenol pyruvate (PEP) concentrations, has been studied in cells of the erythrocytic line. The enzyme from erythrocytes shows positive cooperativity, it behaves as michaelian in reticulocytes and shows negative cooperativity in bone marrow cells. ATP exerts an inhibitory effect in all cases. The activator effect of fructose 1,6-bisphosphate (FBP) was found only in erythrocytes.