Human red cell glycolytic intermediates.

The human red blood cell is readily available in a wide range of quantities and can be processed to a highly purified single cell suspension. It normally converts glucose almost quantitatively to lactic acid, and this conversion appears to be a predominant fraction of the total metabolic activity (1). Because of these characteristics the human red cell provides a convenient material for the study of glycolysis as it functions in an intact mammalian cell. The experimental approach of the present investigation has been based on the expectation that more information concerning the concentrations and turnover rates of the glycolytic intermediates, in normal and experimentally or naturally modified states, would lead to a better understanding of intracellular metabolic controls. The objectives of the study required not only the collection of more accurate analytical values for the intermediates but also the isolation of these compounds in as high a state of purity as possible. This communication describes how several of the metabolic intermediates may be isolated in good yield by column chromatography on ion exchange resins and summarizes the values which were found for their normal equilibrium levels. Considerable detail concerning the identity and purity of the compounds is also presented since most have either not been reported or have not been well characterized previously as components of the red cell. Moreover, this information will be especially important in the interpretation of the isotope labeling experiments to be reported later.