50 THE ALBUMINS. 



Collectively the albumoses which are derived from the true albu- 

 mins, in contradistinction to those which are obtained from the 

 albuminoids, are also termed proteoses. According to their origin, 

 we further distinguish between globulinoses, vitelloses, caseoses, 

 myosinoses, keratinoses, elastoses, gelatoses, etc. One and the same 

 albumin, moreover, can give rise to the formation of different albu- 

 moses. During the decomposition of fibrin, for example, primary 

 albumoses first result, which are then transformed into secondary 

 albumoses, and these into the so-called peptones. Formerly a dis- 

 tinction was made between hemi-albumoses and anti-albumoscs, 

 according to the varying degree of resistance which the individual 

 substances oifered to the action of trypsin. While we still recognize 

 the existence of hemi- and anti-groups in the original albumins, it 

 appears from recent researches that a complete separation of these 

 groups does not occur at the stage of digestion at which the albu- 

 moses only are found. These terms have hence been abandoned. 

 The primary albumoses were formerly also divided into two groups, 

 viz., the proto-albumoses and the hetero-albumoses. We now know, 

 however, that still others are primarily formed, as will be shown 

 later. The term dysalbumose has been applied to a variety of albu- 

 mose which apparently results from the hetero-albumoses when these 

 are dried or kept under water for some time ; dysalbumose is then 

 insoluble in dilute saline solution. 



In their quantitative composition the albumoses very curiously do 

 not differ materially from the original albumins, and it is hence dif- 

 ficult to explain the relationship which exists between the two 

 groups. According to most authorities, the albumoses represent 

 hydrolytic decomposition-products of the albumins, and it has been 

 shown as a matter of fact that through the influence of acetic anhy- 

 dride upon the so-called peptones, which, as we shall presently see, 

 represent the final products of albuminous digestion, albuminate-like 

 substances can be obtained. Others, however, regard the trans- 

 formation of albumins into albumoses as a depolymerization of the 

 original substance, while still others look upon both as isomeric 

 bodies. 



The albumoses give the same color-reactions as their mother- 

 substances. With the biuret test, however, the original violet is 

 absent, and instead a beautiful rose color is obtained. Their final 

 decomposition-products are the same as those of their antecedents. 



Unlike the albumins, the albumoses are not entirely indiffusible, 

 and it appears that the power to pass through animal membranes 

 increases as they become structurally further and further removed 

 from their mother-substances. 



As a class the albumoses are much more readily soluble than the 

 albumins. Most of them are soluble in water or in dilute saline 

 solutions, and also in dilute acids and alkalies. From their solu- 

 tions they are readily precipitated by certain neutral salts, notably 

 ammonium sulphate, which precipitates alt albumoses when added to 



