374 



CHEMISTRY OF THE PROTEIDS 



CHAP. 



very considerably. The most recent estimations by Abderhalden l are 

 as follows : 



2. Plant Caseins. Phyto-vitellines. Legumins. Conglutins 



Under this heading a number of substances have been classified, 

 which are insoluble in water and in salt-solutions, but soluble in dilute 

 alkalies, and precipitable from their alkaline solutions by means of 

 acids. According to Wiman, 2 the legumin of peas contains 0*35 per 

 cent phosphorus, and yields on peptic digestion a pseudo-nuclein. It 

 is therefore a nucleo-albumin, and seems to be identical with the albu- 

 mins of lupines and of other plants described by Palladin 3 and Vines. 4 

 A phosphorus-containing albumin is also contained in wheat, according 

 to Morishima. 5 



Legumin gives the reactions of nucleo-albumins ; it can be coagu- 

 lated only partially, and is denaturalised by alcohol only very slowly. 

 Sulphuric acid, if in excess or on heating, redissolves the precipi- 

 tate ; the biuret-reaction is not violet, but red. Because of this colour- 

 reaction, their nitric-acid reaction, and their partial coagulability, these 

 substances have occasionally 6 been classified with the albumoses, but 

 this is not justifiable. Weyl's 7 plant-myosin, which coagulates be- 

 tween 55 and 60, is, according to Palladin, 3 the lime salt of vitelline. 

 The following vitellines have been investigated more thoroughly : 



(a) The gluten -casein of wheat. It forms the, in alcohol, water, 

 and salt -solutions, insoluble fraction of wheat -gluten. It has been 



1 E. Abderhalden, Zeitsch. f. physiol. Chem. 44. 265 (1905). 



2 A. Wiman, Holy's Jahresber. /. Tierchem. 27. 21 (1897). 



3 W. Palladin, Zeitschr. f. Biolog. 31. 191 (1895). 



4 S. H. Vines, Journ. of Physiol. 3. 93 (1880). 



5 K. Morishima, Arch. f. experim. Path.-u. Pharm. 41. 345 (1898). 



6 S. H. Martin, Journ. of Physiol. Q. 336 (1885). 



7 T. Weyl, Zeitschr. f. physiol. Chem. 1. 72 (1877). 



