CHAP. III.] 



LYSATININE. 



259 



When lysine is heated with Ba(OH) 2 at 150 160 it is not split 

 ip, and can be' again recovered, (Siegfried). When, however, lysati- 

 dne is subjected to the same process, it is split up and barium 



brbonate is formed. Thus is explained the origin (at least in part) 

 )f the C0 2 which is one of the products of Schiitzenberger's process, 



id which is to be looked upon as a secondary product. 

 Drechsel assumes that 1 molecule of lysatinine, when decomposed 



dth caustic baryta, yields 1 molecule of urea, which by further 

 >xidation will yield 1 molecule of CO 2 . From 100 parts of dry 



Ibumin treated by his baryta method, Schiitzenberger obtained a 



laximum quantity of 12* 5 parts of BaC0 3 , which corresponds to 

 i79 parts of CO 2 . These 2'79 parts of C0 2 , on the assumption stated 

 ibove, may have their origin in 8'95 parts of lysatinine, or 3'8 parts 

 )f urea springing from the decomposition of this body, respectively, 

 "'bus from 100 parts of dry proteid matter there probably are 



lerived in the organism 3'8 parts of urea, by processes purely of 

 lecomposition. But how can the relation between the urea formed 

 in this way to the total amount of urea formed by the decomposition 

 of the organism be calculated ? 100 parts of albuminous matter, in 

 round numbers, contain 16 per cent, of nitrogen, which is almost 

 entirely excreted as urea. The 16 per cent, of N correspond to 

 34'3 parts of urea. If we now compare the amount of urea which 

 can be derived from lysatinine directly split off from the proteids, 

 with the total amount of urea which the proteid can furnish in the 

 economy, we arrive at the result that the proportion of the 

 former to the latter is as 1 : 9 (3'8 : 34'3 :: 1 : 9'02). 



How the other nine-tenths probably arise will be matter for 

 discussion in the sequel. 



Lysine and Th exper i ments o f Drechsel, Fischer, and Siegfried 

 lysatinine ac- , , , , i o. Ai 



tuai products na( * snewn that under the JbLul and bnu! 2 process, the 

 of digestion by two bases which we have been considering are formed, 

 trypsin. however varying the nature of the albuminous body. 



Thus Drechsel discovered lysine and lysatinine in the products of the 

 decomposition of casein. His pupil, Fischer, separated these bases 

 by following the same process with gelatin ; and Dr Max Siegfried 

 obtained the same results, working with conglutin, gluten-fibrin, 

 hemiprotein, Maly's oxyprotosulphonic acid and egg-albumin. 



That the decomposition of proteids proceeds as has been stated, 

 when they are subjected to the action of reagents which are capable 

 of splitting them up, will appear to some to afford no sufficient 

 ground for assuming that the same process is likely to occur in the 

 animal economy and, until this is proved, the arguments which have 

 been developed will seem to these objectors to be fanciful and of 

 little value. But direct experiment is no longer wanting to prove 

 that lysine and lysatinine are formed under conditions which neces- 

 sarily must lead to their production in the alimentary canal. 



Dr S. G. Hedin, working under Drechsel, separated from the 



3*5^ 



SRSITY) 



OF THE 

 UNIVERSITY 



