(1) In order to study the relationship between the energy metabolism via TCA cycle and amino acid metabolism as well as protein synthesis, C14-labelled substrates were used for tracer experiment . (2) Considerable C14O2 formation was noted from carbohydrates such as acetate-1-C14, pyruvate-1-C14, and pyruvate-3-C14, while a smaller amount of C14O2 was produced from amino acids such as glycine1-...