6 ELEVENTH REPORT. 



vital forces centering ui^on the cell have given zest to investigations which 

 are wide-reaching. . ., 



While the analj'sis of an enzyme is not within the grasp of man, it is well 

 known by the specific work which it is capable of doing. We may assume 

 that it is a molecular combination which stimulates intra- and inter-molecular 

 changes by various means. When starch is boiled in a weak solution of 

 acid, this polysaccharide is converted into maltose, a disaccharide. This 

 is supposed to represent, simply and cnidely, what nature does through 

 this enzyme by hydrolysis. The changes wrought I:)}' different enzymes as 

 starch to maltose, cane sugar to invert sugars, and fat into glycerin and 

 fatt}^ acids; protein into proteoses, are all looked upon as hydrotytic. There 

 are other changes produced for which enzymes are sponsors; the change of 

 sugar to alcohol which appears to be the splitting of the molecule, the change 

 of alcohol into acetic acid, which means oxidation, and others, many of which 

 are not definitely placed. 



Hill says that an enzyme, maltase, which changes maltose into dextrose, 

 may produce a change diametrically the opposite ; that is, cause the synthesis 

 of dextrose into maltose. Kastle and Leavenhart have ascertained that 

 lipase which converts fat into fatty acids and glycerin accelerates the syn- 

 thesis of fat. If this be true, whether it is the enzyme designated or some 

 other, it is very significant from the view point of the anabolie process of 

 the cell. Loeb says: "We understand how it happens that in times of 

 abundant fat supply, our tissues are able to store up fat, while in times of 

 want fat disai:)pears from them." 



In this manner, the products of fermentation, whether the results of 

 hydrolysis, oxidation, or otherwise, have been taken as the index of the 

 nature' of the molecular structure from which they have been derived. Add 

 to this the possibility of synthesis l^y fermentation, the value of this method 

 of reasoning is not only doubled, but becomes of the greatest importance. 



In the hydrolysis of proteins it is generally conceded that such groups of 

 products respectively occur: proteoses, peptones and amido-compounds. 

 Fischer has shown in recent years that the amino acids may ciuite readily 

 combine in the form of an amide-linking ; that is, two molecules of such a 

 compound as glycocoll or amido-acetic acid l)y the sul)traction of a molecule 

 of water will yield glycyl-glycine. In a similar manner, many amino acids 

 may be combined into what he calls polypeptids, which approach the nature 

 of peptones. Leading from actual demonstration to speculation, it is easily 

 conceived how this same process may, with some modifications, extend 

 through peptones to proteoses, through proteoses to proteins. 



Further, there is added to the knowledge of the degradation and synthesis 

 of protein, the contributions arising from the carefully studied hexon bases 

 which are easily split off from the proteid molecules l^y the action of acids. 

 They are also formed by metabolism, enzymes, and perhaps other proto- 

 plasmic agents. Their ' structural nature upholds the foregoing view of 

 Fischer by extending it and introducing other factors as oxidation. 



The interesting fact that von Baeyer, in 1870, had stated that the carbo- 

 hydrates of plants came by way of the carbon-dioxide of the air through the 

 instrumentality of the chlorophyll of the plant becomes more pertinent in 

 the light of present knowledge. Fischer has shown that formaldehyde, 

 the supposed first product of plant synthesis from carbon-dioxide, can be 

 easily polymerized into a hexose. 



It is only a step farther, walking in a well known region, to follow the pro- 

 ducts resulting in the degradation of the carbo-hydrate and protein from their 



