POISONOUS PROTEINS 



PART I. 



BACTERIAL PROTEINS. 



MATERIAL. Fifteen years ago, after various 

 attempts to secure bacterial cellular protein in 

 large amount, I succeeded with the tanks for 

 massive cultures which have been described 

 elsewhere. The growths thus obtained are 

 freed from extraneous matter by washing with 

 dilute alcohol and then by thorough successive 

 extractions with absolute alcohol and ether. 

 The cellular substance is ground first in porce- 

 lain and then in agate mortars, and passed 

 through fine meshed sieves. Whatever the bac- 

 terium employed the product is a fine white 

 powder. The dilute alcohol removes the ex- 

 traneous matter mechanically held by the 

 growths and the long continued extractions with 

 alcohol and ether remove coloring matters, fats, 

 waxes, and other less known bodies. I have 

 never made a close study of these extractives. 

 These bacterial powders when examined micro- 

 scopically show the individual cells plainly, es- 



