Transaminations with pyruvate and other α-keto acids

Abstract

Alanine formation was observed chromatographically from pyruvate and some L-[alpha]-amino acids, with sedimented particles and with soluble proteins of fresh-rat-liver homogenates. Evidence was obtained that transminations with pyruvate do not proceed via trans-amination to [alpha]-oxoglutarate. For L-[alpha]-amino acids which take part in the reaction, transamination with pyruvate is more rapid than aerobic oxidation in rat-liver preparations. The possibility of oxidative deamination via transamination to pyruvate, for some L-[alpha]-amino acids in rat liver, is discussed. Transaminations with L-alanine and some [alpha]-keto acids were observed. Fresh rat-liver preparations catalyze transaminations with L-[alpha]-amino acid-[alpha]-keto acid pairs, not involving glutamate-[alpha]-oxoglutarate of alanine-pyruvate.