426 



CHEMISTRY OF THE LEUCOMAINS. 



^three bases therefore result as a rule simultaneously in the hydro- 

 lytio cleavage of proteids irrespective as to whether this is induced by 

 acids or by enzymes. From the table given below it will be seen 

 that lysin is not only absent from several protamins but also from 

 the alcohol soluble proteids of wheat and maize. In the latter case 

 it is noteworthy that the absence of lysin is associated with an un- 

 usually large amount of ammonia. Levene and Mendel,' it should 

 be noted, obtained by hydrolysis of edestin, the crystalline proteid 

 from hemp-seed, arginin, histidin and undoubtedly lysin. Accord- 

 ing to Schulze and Winterstein ^ edestin and the proteid from seeds 

 of conifers yields more arginin than do other vegetable proteids. 

 Edestin gave 11 percent, arginin; 1.17 per cent, histidin and 1.3 

 per cent, lysin. 



The splendid researches of Kossel' on the protamins and their 

 cleavage products led to the discovery of histidm, the third hexon 

 base. Undoubtedly, histidin was obtained by Siegfried in his studies 

 on the cleavage products of proteids (1891), but it remained for 

 Hedin * to clearly demonstrate its presence among the hydrolytic 

 products of casein, egg albumin, blood serum and horn. Since then 

 it has been found as a constant cleavage product of the more com- 

 plex animal and plant proteids. 



Recently Kossel and Kutscher ' have carried out a most careful 

 study upon the quantitative distribution of the hexon bases in the 

 different proteids. Their results in per cent, are given in the fol- 

 lowing table : 



Arginin, it will be seen, is a constant constituent, and is by far the 

 most abundant of the hexon bases. The amounts found in several 

 instances are higher than those which Hedin obtained (p. 423). 

 Hedin's results represent the minimum values obtained by a some- 

 what imperfect method. For the amounts of arginin in seeds, sprouts 

 and in elastin see p. 423. 



' Am. Jmim. Phyniol, 6, 48, 1901. 

 "Zeits. physiol. them., 33. 557. 

 ^Zeits. physiol. Chem., 22, 178, 1898. 

 *Zeits. pliygiol. Chem., 22, 191. 

 " Zeits. physiol. Chem., 31, 207, 1900. 



