Oxidation of acetic acid in animal tissue

Abstract

The oxidation of acetate, glycollate, and gly-oxylate in guinea-pig kidney cortex was studied by examining the effect of these substrates on the O2 uptake and the formation of bicarbonate. The oxidation of acetate, as measured by the formation of bicarbonate, was more rapid in guinea-pig kidney cortex than in any other tissue examined. On the avg., O.0156M acetate raised the Q[image]2, by about 50% and Qbic. was +7.6 as compared with a Qbic +1.0 in absence of added substrate. The oxidation of acetate was found to increase with the substrate conc.; it depends on the pH, the highest Qbic. having been found when the pH of the medium was decreased by filling the vessel with 1% CO2 in O2; NH4+ decreased the oxidation of acetate; no bicarbonate was formed under anaerobic conditions. Malonate inhibited the oxidation of acetate in guinea-pig kidney. The inhibition was almost complete at a conc. of 0.031M malonate. Glycine, glycollic acid, and ethanol were not appreciably oxidized in guinea-pig kidney. Glyoxylic acid is a strong inhibitor of tissue respiration. Glyoxylic acid strongly inhibits the decarboxylation of pyruvate by fresh yeast maceration juice. Glyoxylic acid to a small extent may undergo a coupled oxido-reduction in liver and kidney tissue to form glycollic and oxalic acids. It is concluded that neither glycollic nor glyoxylic acid is an intermediate in the oxidation of acetic acid in guinea-pig kidney cortex.