102 PHYSIOLOGICAL CHEMISTRY. 



as compared with the ordinary proteins. They are not coag- 

 ulated by heat and do not give the Millon's reagent reaction 

 or that of Adamkiewicz. The biuret reaction is marked 

 and the alkaloid reagents produce precipitates. Some of the 

 groups in the common proteins are therefore wanting in the 

 protamines. Several of these bodies have been isolated, par- 

 ticularly from the nucleo-proteids of fish spermatozoa and the 

 names given to them suggest their origin. Thus, we have 

 salmin, sturin, scombrin arid clupein. In recent analyses the 

 following formulas have been found for the more important 

 protamines : 



Salmin 

 Clupein 

 Scombrin 

 Sturin 



When warmed with weak acid, or when subjected to pan- 

 creatic digestion, they yield at first protones, corresponding to 

 the peptones of ordinary digestion and finally simpler products, 

 among which the hexone bases, arginine, lysine and histi- 

 dine predominate. From salmin, for example, over 80 per 

 cent of arginine has been obtained. In some cases of decom- 

 position the cleavage into the hexone bases has been nearly 

 quantitative, which is an important step toward establishing 

 the empirical formula of the parent protamine. The prota- 

 mines appear to have rather marked toxic properties. 



The histones are more complex bodies than the protamines, 

 and possibly contain the latter as a component part. It is also 

 possible that the histones represent a stage in the development 

 of the protamines, since while the former are found in imma- 

 ture spermatozoa, the latter are commonly obtained from the 

 mature organisms. The histones are bodies which bear close 

 relation to the albumoses, and show several of the reactions 

 considered as characteristic of the latter. They are water 

 soluble and yield a precipitate with ammonia which is insol- 

 uble in excess in presence of ammonium salts. A pure aqueous 



