182 CHEMISTRY OF THE PROTEIDS CHAP, 



mixtures of deutero-albumoses or albumoses in general are no long 

 of any value. The numerous analyses of Kuhne and Chittenden, 1 

 Kossel, 2 Herth, 3 Thierfelder, 4 and many others, have always yielded 

 figures approaching more or less those of albumins proper ; but no 

 uniformity was to be expected in the figures of different authors, because 

 in such mixtures the individual albumoses varied greatly in amount. 

 The investigations of Haslam, 5 Goto, 6 and Levene 7 have also only 

 shown that in mixtures of albumoses the dissociation -products are 

 present in about the same concentration as in albumins. 



The sequence in which the individual albumoses and peptones are 

 liberated and how they are connected together was first investigated 

 by Neumeister 8 and recently by Zunz. 9 According to the latter 

 dissociation first results in the liberation of three co-ordinated primary 

 products : the prot-albumose, the hetero-albumose, and the gluco- 

 albumose. The peptones and the deutero-albumose C are present even 

 after a long time, i.e. presumably at the end of the peptic digestion. 



That the primary albumoses are converted by further peptic diges- 

 tion into deutero-albumoses and peptones, Neumeister and Pick have 

 proved, but whether the deutero-albumoses are intermediate products 

 and whether they also give rise to peptone, and how many such 

 intermediate substances exist, are questions not yet answered. 



Peptone A seems to be derived from gluco-albumose, the deutero- 

 albumose C from hetero-albumose, and peptone B from protalbumose. 

 No other connection between albumoses is known. During the very 

 first stages of digestion Zunz already observed abiuretic bodies (see p. 1 7), 

 which were apparently peptids. It is possible that these substances 

 along with one or the other of the peptones are liberated directly from the 

 albumin-molecule, while as yet the larger cohering complexes form the 

 primary albumoses. Another possibility is that the albumin as a whole 

 passes through the same changes, namely, primary albumoses, deutero- 

 albumoses, peptones and peptids, but with different rates of rapidity. 



The following substances have been investigated up till now by 

 Pick's method : Crystalline serum- and egg-albumin and serum-globulin 



1 W. Kuhne and R. H. Chittenden, Zeitschr.f. Biol 20. 11 (1884), 22. 423 (1885). 



2 A. Kossel, Pfliiger's Arch.f. d. ges. Physiol. 13. 309 (1876) ; Zeitschr. f. physiol. 

 Chem. 3. 58 (1879). 



3 R. Herth, ibid. 1. 277 (1877). 



4 H. Thierfelder, ibid. 10. 577 (1886). 



5 H. C. Haslam, ibid. 32. 54 (1900). 



6 M. Goto, ibid. 37. 94 (1902). 



7 P. A. Levene, ibid. 37. 81 (1902). 



8 R. Neumeister, Zeitschr.f. Biol. 24. 267 (1888). 



9 E. Zunz, Zeitschr.f. physiol. Chem. 28. 132 (1899) ; Hofmeister's Beitrage, 2. 435 

 (1902). 



