HEXON BASES. 425 



fibrin in the presence of toluol yields not only albumose and pepton 

 but also simpler cleavage products such as arginin, leucin, tyrosin, 

 glycocoU, alanin, phenyl alanin, asparaginic and glutamic acids. The 

 enzyme of B. fluorescens liquefaciens under like conditions gave 

 arginin, leucin and asparaginic acids. 



It is evident from what has been said that arginin and the other 

 hexon bases exist preformed in the proteid molecule and that they 

 are liberated or split off by the action of acids and of tryptic enzymes 

 and by oxidation with potassium permanganate (Jolles). A most 

 interesting question arises as to whether these hexon bases are also 

 liberated in the tissue metabolism of the body. Already Gule- 

 witsch' has shown that the spleen, on standing with thymol for 

 eighteen hours, contains arginin. This may be due to initial hy- 

 drolysis, especially since it is known that the spleen and other organs 

 of the body contains an active proteolytic enzyme (Hedia and Row- 

 land).^ As yet the hexon bases have not been detected in the urine, 

 but it is not unreasonable to suppose, inasmuch as they are unques- 

 tionably antecedents of urea, that they will appear in the urine when 

 normal urea formation is interfered with. The marked resemblance 

 which arginin bears to creatinin and to the leucomains of that group 

 was pointed out from the first by Schulze. 



The second member of the hexon group, lysin, we owe to the 

 brilliant investigation of DrechseP (1890) on the cleavage products 

 of casein. On boiling casein with hydrochloric acid and tin he ob- 

 tained ammonia, amido acids, and two bases lysin and lysatinin. 

 Fischer, a pupil of Drechsel, obtained the same products by hydro- 

 lyzing gelatin in like manner (Inaug. Diss. 1890). Subsequently, 

 Siegfried^ showed that a number of proteids, conglutin, gluten- 

 fibrin, hemiprotein, oxyprotosulfonic acid and egg albumin also 

 yielded the two bases found by Drechsel. Hedin isolated lysin 

 from horn, casein, conglutin, egg albumin, yolk albumin, and blood 

 serum. By employing the same method Schwarz" obtained from 

 the elastin of the aorta some lysatinin. In 1895, however, Hedin' 

 showed that lysatinin was really a mixture of equal molecules of 

 lysin and arginin. Since then lysin has been found associated with 

 arginin and histidin in various proteids of animal origin with the 

 exception of the several protamins indicated in the subjoined table. 

 Its presence in " antipepton " and in tryptic digestion of fibrin and 

 sturin has already been referred to. Schulze^ rounded out his 

 studies on arginin in plants by showing that both lysin and histidin 

 were also present in lupine sprouts and in the seeds of the fir. The 



' Zeits. physiol. Chem., 30, 533 (1900). 



'Zeits. physiol. Chem., 32, 341, 531, 1901. 



'Berichte, 23,3096. 



*Benchle, 24, 418, 1891. 



^ Zeits. physiol. Chem,., 18, 487. 



^Zeks. physwl. Chem., 21, 297, 1895 ; 20, 186. 



''Zeits. physiol. Chem., 28, 459, 465. 



