THE PRESENT SIGNIFICANCE OF THE AMINOACIDS IN PHYSIOLOGY AND PATHOLOGY

Abstract

CHEMICAL NATURE OF THE AMINO-ACIDS This discussion is inserted because it will be necessary, for the ready understanding of the later parts, that speaker and audience shall have in mind from the same point of view two or three significant chemical characteristics of the amino-acids as a class. We know, chiefly as the result of the researches of Fischer,¹ Kossel, and their collaborators, that the amino-acids are the units or building stones out of which the protein molecule is constructed. They are the final products obtained when proteins are hydrolyzed by strong acids, or by the action of pepsin, trypsin and erepsin in the alimentary canal. In the characteristic points of their structure the amino-acids are all alike. That is, they belong to a type, and we have only to understand the type in order to become fairly well acquainted with them all. We have pictured in Figure