The Ferment-action of Bacteria* 



547 



the action of the enzyme, a modification of the process was next 

 made in the following manner : — 500 c.c. of meat broth were inocu- 

 lated with the microbes, and left in the incubator for seven days. 

 The precipitate, with an excess of alcohol, was allowed to stand 

 overnight, and, after drying, was dissolved in sterile distilled water, 

 and then reprecipitated by alcohol. This precipitate was dried and 

 taken up in distilled water. The next day about 20 c.c. were added 

 to 100 c.c. of a 5 per cent, gelatine, and placed in the incubator at 

 37° C. 



Results after four days : — 



The only positive results were obtained with the scurf bacillus and 

 the Welford bacillus. In these cases the gelatine remained liquid, 

 while the control gelatine resolidified. The control plates gave no 

 colonies. 



Conclusion, — The bacteria do form a soluble enzyme which can be 

 isolated, and its action demonstrated on albumenoid gelatine. 



V. 



Are the microbes which liquefy gelatine capable of exerting a like 

 action on other proteid bodies ? 



To test this, experiments were made with — 



(a.) Egg-albumen. 

 (&.) Fibrin. 



In the first place, it was necessary to find out what resulted from 

 the direct action of the microbes. 



Faintly alkaline meat broth, as developing the most active enzyme, 

 was used. 



(a.) Egg Albumen. 



To flasks containing 100 c.c. of meat broth were added small 

 pieces of coagulated egg albumen. The flasks were then sterilised 

 and inoculated with Koch's spirillum, Finkler's spirillum, the scurf 

 and Welford bacilli. They were then placed in the incubator at 

 37° C. 



Results : — 



(1.) Scurf bacillus. 



Welford bacillus : — 



1st day. No marked change. 



2nd day. Albumen broken up iuto small fine flocculent 



fragments. 

 3rd day. Disintegration almost complete, 

 4th day. Disintegration complete. 



2 o 2 



