The role of red cell membrane in the regulation of glycolysis and the 2,3-bisphosphoglycerate-cycle.

Pyruvate and K-ferricyanide stimulation of net ATP and 2,3-bisphosphoglycerate synthesis is very probably due to enhancement of glyceraldehyde 3-phosphate dehydrogenase activity. Significant peculiarities in the K-ferricyanide effect and its depression by non-penetrating-SH inhibitors at low concentrations were noted and suggested that membrane-bound enzymes play a substantial part in the synthesis of ATP and 2,3-bisphosphoglycerate. Experiments with isolated ghosts showed their ATP-and 2,3-bis-phosphogylcerate-building capacity. Pulse-labeling with 32P-Pi and determination of specific radioactive in intracellular inorganic phosphate and ATP-gamma-P demonstrated that the ferricyanide-stimulated compartment utilizes only intracellular inorganic phosphate for ATP (and 2,3-bisphosphoglycerate) synthesis, and does so only when extracellular inorganic phosphate is present.