I 66 BACTERIA 



MUCOSUS CAPSULATUS GROUP 



There is a large group of organisms of moderate pathogenic 

 powers and importance called variously, Bacterium aerogenes, 

 Bacterium mucosus or Aerogenes mucosus group of which the 

 Friedlander bacillus is the most important. They all have a 

 luxuriant growth on media; are negative to Gram stain; ferment 

 most of the carbohydrates; are non-motile and most of them 

 show a capsule when in the animal body. 



Perkins divides them as follows: 



I. Bacterium aerogenes type ferments all carbohydrates with 

 gas. 



II. Bacterium pneumoniae group ferment all carbohydrates but 

 lactose, with gas. 



III. Bacterium lactis aerogenes group ferment all carbohydrates 

 except saccharose, with gas. 



These organisms are important members of the intestinal flora. 



Bacterium Pneumoniae. 



Friedlander 's Pneumonia Bacillus. 



Morphology and Stains. Short plump rods with rounded ends, 

 surrounded by a thick gelatinous capsule .in animal fluids, and 

 when grown in milk; is not motile, and has no spores; does not 

 stain by Gram's method, but easily by the common basic dyes. 



Oxygen Requirements. Grows in and without oxygen, upon 

 all culture media. 



Chemical Activities. Produces abundant acids, COz and H, 

 gas, alcohol, indol, ferment and H 2 S. 



Habitat. Has been found in soil; sometimes in healthy saliva. 



Culture Media. Grows luxuriantly on all culture media. 



On gelatine it grows in roundish elevated colonies that are 

 yellowish-white with a slimy lustre, and never liquefies the gela- 

 tine. In agar it multiplies even more abundantly with a moister 

 growth. The border of streak cultures is smooth and wavy, and 

 the water of condensation is cloudy. In bouillon the growth is 



