Amino-acids in Nutrition and Growth.’

The current trend of the investigation of the chemistry of nutrition is emphasizing the significance of the amino-acids as the fundamental factors in all problems in which hitherto the r61e of proteins has been involved. The remarkable success which has at’tended the efforts to supplant completely the proteins in the food intake by their ultimate products of hydrolysis-the so-called amino-acid “Bausteine’‘-has led to promising researches in which these food fragments have been followed beyond the alimentary barrier into the blood stream, to the tissues, and almost to their final destruction in the body. The question of protein synthesis has now become a problem of the biochemical deportment of amino-acids. By Abderhalden’s well-known experiments in this field of study it has been demonstrated that dogs (and even man) can be maintained in nitrogenous equilibrium, or, in some instances, can even gain weight and retain nitrogen when completely digested protein supplies the nitrogenous component of the diet.2 Furthermore