Bacillus Butyricus, Hueppe. 



ORIGIN. Milk. 



FORM. Long-, narrow rods, with rounded ends, fre- 

 quently in pairs, may form threads. 



MOTILITY. It is actively motile. 



SPORULATION. At about 30 it forms bright, oval, median 

 spores. 



ANILIN DYES. React well. 



GROWTH. Rapid. 



Gelatin plates. The deep colonies form yellowish masses, whereas 

 the surface ones liquefy rapidly and then form grayish-brown, granu- 

 lar patches with fibrillated borders. 



Stab culture. Slow liquefaction along- the entire line of inoculation. 

 The gelatin becomes colored yellowish and on the surface a thin, 

 folded, grayish-white scum forms. The liquid remains cloudy for some 

 time, but later the growth settles to the bottom. 



Streak culture. On agar, it forms a thick, grayish or yellow, sticky 

 covering-. On potato, a light brown, transparent growth results which 

 sometimes becomes folded. 



Milk. Without chang-e in the amphoteric reaction the casein 

 gradually coagnlates, as with rennet. Subsequently, after about 8 

 days, the casein is redissolved or peptonized with formation of pepton, 

 leucin, tyrosin, ammonia and bitter products. From hydrated milk 

 sugar and lactates it forms butyric acid. 



OXYGEN REQUIREMENTS. It is aerobic. 

 TEMPERATURE. It can grow at the ordinary temperature, 

 but its optimum is at 35 to 40. 



BEHAVIOR TO GELATIN. It liquefies gelatin. 

 AEROGENESIS. Butyric acid is formed. 

 PATHOGENESIS. It has no effect on animals. 



A large number of aerobic and anaerobic bacteria give 

 rise to butyric acid fermentation (see p. 103). The vibrion 



butyrique of Pasteur was the first anaerobe discovered (1861). 



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