70 THE CHEMICAL CONSTITUTION OF THE PROTEINS 



Protamines. 



The first work upon this group of proteins was carried out by 

 Miescher [1874], who described the basic substance protamine 

 present in the sperm of salmon. Piccard [1874] made similar in- 

 vestigations. Kossel extended the work of Miescher by examining 

 the basic proteins in the sperm of other fishes. He termed the 

 whole group protamines, the individual members being called 

 salmine, sturine, clupeine, etc., according to the name of the fish from 

 which they were prepared. 



The first analyses of salmine and sturine [Kossel, 1896-97] were 

 qualitative and showed the presence of arginine and histidine with 

 quite small amounts of mono-amino acids. Lysine was found later 

 in sturine [Kossel, 1898], and it was thought that the protamines 

 contained the three bases as their principal constituents, but Kossel 

 [1898-99] with improved methods of analysis showed that arginine 

 only was present in salmine and clupeine, whereas sturine contained 

 all three hexone bases. Subsequent work by Kossel [1898-99, 

 1903], Morkowin [1899], Kossel and Dakin [1903-4, 1904, 1905] was 

 devoted to the identification of the mono-amino acids. Quantitative 

 analyses of the di-amino acids were made by Kossel and Kutscher 

 [1900-1], and Kossel and Dakin [1904] published a complete analysis 

 of salmine. Their result does not conform to that of Abderhalden 

 [1904] and the difference is to be attributed to the material analysed ; 

 Abderhalden probably used salmine prepared from unripe sperm and 

 not sufficiently purified ; Kossel and Dakin used carefully purified 

 salmine from ripe sperm. 



A large number of protamines have been analysed by Kossel 

 [1910, 1913] and the nature of the mono-amino acids determined 

 in some of them by Kossel and Edlbacher [1913]. Some of these 

 were previously investigated by Ulpiani [1902], by Dezani [1908], 

 and by Taylor [1908-9]. Maleniick [1908] prepared sturine from the 

 Russian sturgeon, but did not analyse its constituents. His method 

 of preparation was criticised by Kossel [1910]. Kossel [1913] did 

 not give the actual quantity of the units in these protamines, but 

 determined the percentage of the total nitrogen present as arginine- 

 nitrogen, histidine-nitrogen, mono-amino acid-nitrogen. The arginine- 

 nitrogen on the average was about 80 per cent, of the total nitrogen, 

 the mono-amino acid-nitrogen about 10 per cent. Lysine was absent 

 and histidine present only in percine. 



The analyses show that the protamines are built up almost ex- 



