Cytoplasmic pH and glycolysis in the Dictyostelium discoideum cell cycle

Abstract

Lactate production measurements during the cell cycle of synchronized populations of Dictyostelium discoideum cells reveal cyclic variations in glycolysis which correspond with pH i oscillations which were discovered by us previously [(1985) Cell, in press]. Aerobic lactate production varies about 6-fold during the cell cycle and the lactate maxima correlate with (~ 0.25 pH unit) cyclic increases in pH. However, artificially altering pH i using weak acids or bases does not influence the rate of lactate production in asynchronous cell populations. This result suggests that the cyclic variations in pH i and those in glycolytic rate are not causally related events.