THE ANAREOBIC BACILLI 761 



Proteolytic Group. The organisms of this group can never 

 produce gas gangrene without the presence of one or more bacilli 

 of the saccharolytic group. The members of the proteolytic group 

 digest milk without the formation of a clot and liquefy and often 

 blacken coagulated serum. These two characteristics together with 

 the fact that cultures of the proteolytic organisms usually have a 

 very offensive odor, make it comparatively easy to distinguish them 

 from the saccharolytic group. Sugars are fermented by the pro- 

 teolytic type, but much less rapidly and with the production of 

 less acid and gas than in the case of the saccharolytic group. The 

 members of the proteolytic group produce spores readily in all 

 media. None of these organisms are very pathogenic and produce 

 no general picture of toxemia in spite of the tremendous liquefaction 

 of tissue caused by them. The ferments 28 of several of the pro- 

 teolytic anaerobes have been isolated and have been found to split 

 proteins to animo acids so rapidly that there is no time for the 

 intermediate products to intoxicate the animals. The separation 

 of the proteolytic anaerobes from the saccharolytic is extremely 

 difficult. The members of the two groups are usually present to- 

 gether, arid what will seern to be a pure culture of a saccharolytic 

 organism if held for any length of time, will often show a con- 

 tamination with a proteolytic organism. The best methods for 

 separation of the two groups are : by rapid transplantation in sugar 

 media, where the saccharolytic organisms outgrow the proteolytic, 

 combined with frequent plating, or by animal inoculation. The 

 latter is the most satisfactory. In the animal body after intramus- 

 cular injection, the more pathogenic organisms belonging to the 

 saccharolytic group frequently invade the blood stream and may 

 be isolated from the heart's blood. 



B. sporogenes. This organism was next to B. Welchii most 

 frequently found in wound cultures. Weinberg and Seguin isolated 

 it in 27 per cent of their cases. B. sporogenes was the anaerobe 

 usually responsible for the foul odor of wounds. According to most 

 authors, the pathogenicity of this organism is negligible. Weinberg 

 and Seguin claim to have isolated a few toxic strains, but these 

 may possibly have been mixed with members of the saccharolytic 

 group. Heller has not found any proteolytic anaerobes that are 

 pathogenic for animals. 



23 Blanc and Pozerski, Compt. Rend. Soc. Biol., 87, 1920, 29. 



