BACTERIAL PROTEINS 19 



Ten per cent solutions of potassium hydroxide 

 at 120 extract from bacterial cell substance 

 everything except the chitin-like body which 

 consists of a carbohydrate combined with nitro- 

 gen. 



We have demonstrated the presence in bac- 

 terial cellular substance of both mono and dia- 

 mino acids and have shown that the percentage 

 of these varies with the microorganism. We 

 have found the percentage of nitrogen to vary 

 from 5.964 in subtilis to 11.765 in violaceous. 



I began this work with the expectation of find- 

 ing the bacterial cell substance composed of rel- 

 atively simple bodies. I have been compelled to 

 come to the opposite conclusion. The cellular 

 substance of bacteria contains highly complex 

 molecules. We have demonstrated the presence 

 of the following groups among the split prod- 

 ucts: (a) A chitin-like body consisting of a car- 

 bohydrate combined with nitrogen. It seems 

 reasonable to infer that this exists in the cellu- 

 lar substance as a glyco-protein. (b) A car- 

 bohydrate group combined with phosphorus 

 from which it is not easily detached. This group 

 reduces copper after prolonged boiling with di- 

 lute mineral acid. The amounts as determined 

 by the reduction of Fehling's solution and cal- 

 culated as xylose are large, but we are not sure 



