86 PROTEIN POISONS 



senting 3.7 grams of leucin and 12.4 grams of valin. Prolin 

 was not present. 



Fraction III. From this there was secured by the 

 formation of the copper salt 5.4 grams of leucin and 10.6 

 grams of valin. 



Fractions II and III gave a combined yield of 9.1 grams of 

 leucin and 23 grams of valin, equivalent to 1.82 per cent, 

 of leucin and 4.6 per cent, of valin in the cellular substance 

 or 2.04 per cent, and 5.17 per cent, respectively in the 

 moisture-free substance. 



Fractions IV and V. Each was shaken with three times 

 its weight of cold water and filtered through a damp paper, 

 leaving a brown oil. The oil, after being washed twice 

 with cold water, was saponified with excess of baryta. 

 From this there was obtained 2.5 grams of crude phenyl- 

 alanin. This was purified and the melting-point found to 

 be 263. The yield of phenylalanin amounted to 0.5 per 

 cent, of the cellular substance or 0.56 per cent, of the 

 moisture-free substance. From the filtrate from the oil a 

 few crystals which were probably glutamic acid, were 

 obtained, but the amount was too small for identification. 



From 500 grams of the cellular protein of the bacillus 

 tuberculosis the following substances in the amounts and 

 percentages given were obtained. 



It will be seen that of the total of 40.3605 grams of nitrogen 

 in the fluid esterified there has been recovered in the form 

 of mono-amino-acids only 5.2 grams of nitrogen or 12.88 

 per cent. However, under the best conditions one cannot 

 hope to obtain more than a part of the mono-amino-acids 

 present and the diamino-acids probably take up a consider- 

 able part of the nitrogen. 



