CHAPTER XXX 

 BACILLUS PROTEUS VULGARIS 



Bacillus proteus vulgaris is one of the common organisms of putrefaction. 

 It occurs in air, soil and water, and is present wherever putrefaction takes place. 

 It splits proteids into their simplest components. 



In morphology, motility and staining it is indistinguishable from the colon 

 bacillus. It is differentiated from the colon bacillus by the following 

 characteristics : 



Optimum growth at 25C. 



Liquefies gelatin and blood serum. 



In milk it causes coagulation and then liquefies the clot. 



It is agglutinated with the serum of immunized animals. 



Toxin. Bacillus proteus vulgaris produces little, if any, toxin. ' 



Pathogenesis. This organism is not pathogenic for man, but is of impor- 

 tance on account of the frequency with which it contaminates and putrefies meat 

 and other putrescible foods exposed to air and stored at room temperature. In 

 the process of putrefaction it liberates compounds, some of which are toxic. 



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