DIAMINO-ACIDS. 



165 



bases we will refer to STEUDEL in ABDERHALDEN'S Handbuch der biochem- 

 ischen Arbeitsmethoden, Bd. 2, II, s. 498. 



We give below a tabulation of the amounts of the three hexone bases 

 found in certain protein substances (in weight per cent) : 



Arginine. 



Sturine 1 58.2 



Cyprinine (a) 6 4.9 



Other protamines l 62 . 5 87 . 4 



Histones * 14.3615.52 



Casein 2 4.70 4.84 



Syntonin (from meat) 2 5 . 06 



Heterosyntonose 2 8 . 53 



Protosyntonose 2 4 . 55 



Edestin 3 ... 11.014.07 



Proteid from conjferae seeds 3 



Gluten casein l 



Gluten proteins 



10.911.3 

 4.4 



2.75 3.13 

 Gelatin" 1 and 2 . . ... 7.62 9.3 



Elastin 



0.3 



Of the oxydiamino-acids found on the hydrolysis of proteins we will 

 mention the following: 



Oxydiaminosebacic acid, (?) CioH 2 oN 2 05, has been isolated by WOHLGEMUTH 6 

 from a nucleoprotein of the liver. The free acid was obtained as small white 

 plates. It is soluble with difficulty in hot water, insoluble in cold water and 

 in alcohol. It was optically inactive in hydrochloric acid. The beautifully 

 crystalline phenylcyanate compound had a melting-point of 206. 



Dioxydiaminosuberic acid, CgHieNuOe, has been obtained by SKRAUP 7 on the 

 hydrolysis of casein with hydrochloric acid. The copper salt crystallizes hi 

 beautiful deep bluish-violet rosettes which are composed of long, irregular, right- 

 angled plates. It is quite soluble in cold water. The free acid crystallizes in 

 fern-like formations. Besides this acid SKRAUP obtained two other acids which 

 he calls caseanic acid, CgHie^Or, and caseinic acid, daEUNsOe. The caseanic 

 acid crystallizes, melts at 190-191, is tribasic, and is probably an oxydiamino- 

 acid. The caseinic acid is dibasic and occurs in two modifications. The one 

 which melts at 228 is faintly dextrorotatory; the other modification melts 

 at 245 and is optically inactive. Both crystallize, but the inactive form does 

 not yield well-defined crystals. Caseinic acid seems also to be an oxydiamino- 

 acid. 



Diaminotrioxydodecanoic acid, CiaH^^Os, is an acid obtained by FISCHER and 

 ABDERHALDEN 8 on the hydrolysis of casein and seems to stand close to SKRAUP'S 

 caseinic acid, but differs from it in its optical properties. This acid is faintly 

 levorotatory : (<*) D = about 9. It crystallizes in plates, which grow into rosettes 



1 Kossel and Kutscher, Zeitschr. f. physiol. Chem., 31. 



2 Hart, ibid., 33. 



3 Schulze and Winterstein, ibid., 33; see also Kossel, Ber. d. d. chem. Gesellsch., 

 34, 3236. 



4 Kossel and Kutscher, Zeitschr. f. physiol. Chem., 25, and Richards and Gies, 

 Amer. Journ. of Physiol., 7. 



6 Kossel and Dakin, Zeitschr. f. physiol. Chem., 40. 



6 Ber. d. d. chem. Gesellsch., 37, and Zeitschr. f. physiol. Chem., 44. 



7 Zeitschr. f. physiol. Chem., 42. 



8 Zeitschr. f . physiol. Chem., 42. 



