Activating Effect of Adenosine-5′-Triphosphate on the Neutral Proteolytic Activity of Liver Homogenates 1

Summary

The addition of all the nonessential amino acids in general, and aspartic acid in particular, of ATP, and of small amounts of “amino acid activating enzymes” to liver homogenates produced a definite increase in the rate of protein degradation. The activating effect of the amino acids was shown to be dependent on the presence of ATP and the activating effect of the “amino acid activating enzymes” was shown to be dependent upon the presence of aspartic acid. It was concluded that the activating species may be the aspartyl adenylate which would provide an intermediary between protein synthesis and protein degradation.