OCCURRENCE AND CONTROL OF THE PHOSPHOGLUCONATE OXIDATION PATHWAY IN NORMAL AND LEUKEMIC LEUKOCYTES

Abstract

The phosphogluconate pathway occurs in leukocytes, though less than 10 per cent of utilized glucose traverses this pathway. This per cent is higher in leukemic than in normal cells. The extent of phosphogluconate pathway metabolism is shown to be under direct control of the hexokinase level. The concentration of triphosphopyridine nucleotide and the efficiency of dihydrotriphosphopyridine- oxidizing systems also play a role in the control of phosphogluconate pathway metabolism but a secondary one, particularly in the steady state. The higher percentages of phosphogluconate pathway metabolism in leukemic cells are attributed to their deficiencies of hexokinase. Normal and leukemic leukocytes contain transaldolase and transketolase. The observed levels of phosphogluconate pathway metabolism were the same in homogenized and in intact cells. (auth)