92 PROTEIN POISONS 



identifying them as glutamic acid, C 5 H 9 NO 4 , which has 9.52 

 per cent, of nitrogen. Frankel gives the melting-point of 

 glutamic acid as 202 to 202.5, or quickly heated, 213, with 

 decomposition. The product above obtained melted in an 

 open tube at 242 to 245, in a closed tube at 236 to 238. 

 From fraction 1 of the typhoid poison was obtained alanin, 

 with characteristic properties, as described above. These 

 crystals showed 15.633 per cent, of nitrogen and melted 

 at 267 to 271. Fractions 2, 3, 4, and 5 contained only 

 valin, which showed 11.932 per cent, of nitrogen, the average 

 of four determinations. This melted at 287 to 290.6 in 

 an open tube, 278 to 280 in a closed one. From fraction 6 

 the qualitative test for phenylalanin was obtained as from 

 the tubercle poison. 



Owing to the small yield of esters and crystals, fractions 

 1 and 2 from the colon poison could only be determined 

 qualitatively. Both fractions, however, showed needle- 

 shaped crystals and a sweet taste, which in conjunction with 

 the temperature at which their esters distilled indicated 

 alanin. Fractions 3 and 4 gave characteristic valin crystals 

 containing 11.942 per cent, of nitrogen and melting at 

 283.4 to 285 in an open tube, or 274 to 277 in a closed 

 tube. Phenylalanin was obtained qualitatively from this 

 as from the two preceding poisons. After its extraction 

 from fraction 5, and after saponification with barium 

 hydrate and its removal, crystals in the form of rhombic 

 plates and prisms, insoluble in alcohol, were obtained. 

 These corresponded with those of aspartic acid, and as the 

 quantity was not sufficient for purification by recrystalli- 

 zation, the copper salt was formed with copper acetate. 

 This was obtained in the form of needles, very difficultly 

 soluble in cold water, difficultly in hot, which again 

 corresponded with the properties of aspartic acid. 



When the crystals from the fractions obtained from 

 albumin poison were examined the result was not different. 

 Fractions 1 and 2 produced characteristic alanin crystals 

 with 11.75 per cent, of nitrogen, the average of four deter- 

 minations. The melting-point was 277 to 279.6. Valin, 



