The hierarchical organization of autocatalytic reaction networks and its relevance to the origin of life
Fig 5
(S)-lactic acid may catalyze pyruvic acid carboxylation.
(A) Direct carboxylation of pyruvic acid generates oxaloacetic acid. (B) Indirect carboxylation of pyruvic acid is also possible. Carbon dioxide reacts with (S)-lactic acid first to generate (S)-malic acid, and then (S)-malic acid reacts with pyruvic acid to generate oxaloacetic acid and regenerate (S)-lactic acid. (C) If the composite reaction rate of the direct carboxylation is lower than that of the indirect carboxylation, we may say that (S)-lactic acid can catalyze the carboxylation of pyruvic acid.