The ChemicPvl Basis of Life. 



That the fundamental life processes must 

 "be due, either wholly or partly, to specific 

 chemical structures is generally conceded, "but there 

 is a prevailing opinion that the oheminal structures 

 which are necessary for this purpose must he extreme- 

 ly complex. There is, hov/ever, no very sound founda- 

 tion for this opinion. The compl ex structures observed 

 in the highar plants and animals are the result of 

 evolution, and the fact that they are indispensihl e 

 to the proper physiological functioning of certain 

 higher organisms dees not prove that they are the real 

 cause of the fundamental life processes in the lower 

 organisms. If extremiCly complex structures T7ere 

 necessary for life of any sort, then it would he 

 highly imprcbahle that life could ever have originated 

 spontaneously. 



It seems mere reasonable to assume that life 

 is due tc s 3me comparatively aimple principle of 

 chemistry which has not yet heen discovered. To find 

 the clue to this we must investigate the mol ecular 

 structure of proteins, hecattaB proteins constitute 

 nearly all the solid matter in the "bodies of uni- 

 cellular orgajiisms after removal of the water. 



All protein substances, upon hydrolytic 

 decomposition, yield a mixture of amino acids having 

 the follov/ing molecular structure; 



NHg-CRH-CO-CH, 



where R may he any one of vai*ious complex groups. 

 (E. Klarmann, Chemical Reviews, Vol. IV, p 51, 1927) 



These amine acids will readily condense, 

 with the elimination of water, to form either chain 

 structures known as polypeptides, or ring structures 

 known as diketopiperazines : 



