Mathematical model of pyruvate kinase of chicken erythrocytes.

The PK in mammals is different with regard to molecular structure and kinetic properties from PK in avian hepatocytes (1). Our studies show that the same isoenzyme of PK occurs both in red blood cells and hepatocytes. The PK of human erythrocytes belong to the L-type, that of chicken erythrocytes to the K-type. Both isoenzymes are characterized by cooperative regulation. Allosteric behavior is more pronounced for the chicken enzyme than for that of human erythrocytes. Chicken erythrocyte PK is activated by serine and exhibits a high FDP affinity.