ALBUMINS OR PROTEINS. 



175 



7. GROUP OF THE PROTAMINES. 



The protamines, as we have already mentioned, have been very carefully 

 studied by A. Kossel and his students. They are mainly composed of 

 di-amino acids. It is only recently that mono-amino acids have been 

 detected in the protamines. A. Kossel l states that the protamines con- 

 tain only small quantities of specific mono-amino acids. An observa- 

 tion somewhat at variance with this, was made 2 in a very carefully 

 purified sample of salmine, but this may be explained perhaps by an 

 immature condition of the testes from which the preparation was obtained. 

 We have already mentioned that as a matter of fact the amounts of 

 di-amino acids isolated from the proteins in the testes of the salmon 

 depend on the maturity of the latter. It is very probable that the 

 protamines, which evidently can be traced back to the proteins of 

 the muscles, are formed from histons, which are to be considered as the 

 transition stage in the transformation from the proteins of the muscles 

 to the protamines. The salmine investigated contained alanine, leucine, 

 and a-proline, while phenylalanine and aspartic acid were also, undoubt- 

 edly, present. 



Kossel and his students give the following amino acids as the constituents 

 of the protamines: 



1 Cf. A. Kossel: Z. physiol. Chem. 40, 311 (1903). A. Kossel and H. D. Dakin: ibid. 

 40, 565 (1904); 41, 407 (1904). 



2 E. Abderhalden: ibid. 41, 55 (1904). 



