Abstract: | A qualitative variant of erythrocyte and liver pyruvate kinases (PK Osaka) was detected in a family in which two siblings have extremely low PK activity by semipurification with DEAE cellulose chromatography and subsequent concentration of the enzyme solutions. This was previously reported to be a quantitative variant based on studies of crude tissue preparations. The molecular aberrations were characterized by slow mobility upon electrophoresis, abnormal kinetics for phosphoenolpyruvate, and low affinity for anti-human erythrocyte PK serum. The mutant PK L was similar both electrophoretically and immunologically to PK R. |