Characteristics of a new abnormal variant of G-6-PD in human red cells

Abstract

Kinetic and electrophoretic properties were studied in 230--300 fold purified preparations of glucose-6-phosphate dehydrogenase (G-6-PD) from red cells of donors and patients with hemolytic anemia induced by G-6-PD deficiency. In abnormal variant of G-6-PD isolated from red cells of a patient with hemolytic anemia which had not before been described in the literature was found. The abnormal variant differs from the normal enzyme by a decreased Michaelis constant for G-6-P and NADP, by increased utilization of substrate-analogues (2-deoxy-G-6-P and deamino NADP in particular), by low heat stability, the character of pH dependence, and by the appearance of one band of G-6-PD activity during electrophoresis in polyacrylamide gel. The isolated abnormal variant of G-6-PD has been called "Kremenchug" according to the origin of the patient.