COMPOSITION OF THE BACTERIAL CELL 



61 



LYONS. 



Medium A agar, 1.5 per cent.; peptone, 1 per cent. 

 Medium B agar, 1.5 per cent.; peptone, 5 per cent. 

 Medium C agar, 1.5 per cent.; peptone 1 per cent.; dextrose, 5 per cent. 



It will be seen that the nitrogen content of the bacteria grown in 

 a medium containing nitrogen plus carbohydrate is almost 25 per cent, 

 less than the nitrogen content in the same organisms grown- in the same 

 nitrogen medium but with no carbohydrate. The nitrogen content is 

 greatest in the carbohydrate-free medium, the extractives are greater 

 in the carbohydrate-containing medium. This decrease in the nitrogen 

 content in pathological bacteria grown in sugar media may be of 

 considerable importance, particularly in the preparation of vaccines 

 and other antigens. Nothing is known definitely of the distribution 

 of nitrogen in bacteria, but this reduction of 25 per cent, in the 

 nitrogen content may well influence somewhat the immunizing value 

 of vaccines. 



C. COMPOSITION OF THE MORPHOLOGICAL COMPONENTS OF 

 THE BACTERIAL CELL. 



1. Cell Membrane. Typical cells of higher plants contain cellulose, 

 and bacteria were formerly differentiated sharply from the plant 

 kingdom because cellulose could not be found in them. Later observa- 

 tions would suggest that cellulose or substances chemically closely 

 related to it are demonstrable in certain bacteria. Dreyfuss 2 appears 

 to have identified cellulose in bacteria from pus and. in B. subtilis; 

 Hammerschlag 3 claims to have isolated cellulose from tubercle bacilli, 

 Dzierzgowski and Rekowski 4 appear to have found cellulose in diph- 

 theria bacilli; more recently Tamura 5 has demonstrated a hemi-cellulose 



1 From water. 



2 Ztschr. f. phys. Chemie, 1893, xviii, 375. 



3 Sitzber. Akad. Wiss., Wien, xiii, 12. 



4 Arch. Soc. Biol., St. Petersburg, 1892. 



B Ztschr. f. phys. Chem., 1914, Ixxxix, 289. 



