Glucose metabolism and dehydrogenase activities in the cytosol and mitochondria of mouse LS cells in chemostat culture.

Energy metabolism has been examined in mouse LS cells growing under steady-state conditions in chemostat culture. The metabolic quotient of glucose oxidized (glucose consumed, but not fermented) remained constant, independent of growth rate between cell doubling times of 6 days and 1.2 days. Specific activities of cytochrome oxidase and malate dehydrogenase in the mitochondria remained constant at different growth rates, in accord with the constancy of the glucose oxidation rate. Cytosolic malate dehydrogenase activity was about fourfold greater than the mitochondrial isozyme. The steady-state rate of lactate production fluctuated because of technical limitations but correlated well with cytosolic lactate dehydrogenase activity.