688 



ORDER IV. EUBACTERIALES 



ing with the medium, spherical, terminal, 

 swelling the cells. Young cells are motile, 

 the motility disappearing with sporulation; 

 flagella not demonstrable. Young vegetative 

 cells are colored wine-red with iodine solu- 

 tion. Gram-positive, becoming Gram-labile 

 on sporulation. 



Gelatin (plus asparagine) : Liquefaction 

 in 6 to 10 days. Medium remains perfectly 

 clear. 



Asparagine agar deep colonies: Grayish 

 white, delicate, cottony, with fine radial 

 outgrowths. 



Asparagine agar surface colonies (ana- 

 erobic): Poor, delicate, translucent, filmy, 

 scarcely discernible growth. 



Cellulose-liver broth: Solution remains 

 visibly clear and does not darken with age. 

 Occasionally, large gas bubbles arise. 



Milk: Soft coagulation in 24 hours. Amor- 

 phous clot shrinks and settles, forming a 

 yellowish red to orange sediment with tur- 

 bid supernatant whey. 



Indole not produced. 



Hydrogen sulfide produced in trace 

 amounts in inorganic solutions. 



Maltose, mannitol, lactose, glucose, su- 

 crose, galactose, fructose, starch, salicin, 

 glycerol and inulin not attacked. 



Cellulose, apparently the primary carbon 

 source, is only weakly attacked by pure cul- 

 tures with the production of hydrogen and 

 carbon dioxide. Yellow pigment not ob- 

 served in the presence of cellulose (see Clos- 

 tridium dissolvens) . 



Nitrites not produced from nitrates. 



Ammonia not produced. 



Brain medium: No digestion or blacken- 

 ing. No visible evidence of growth. 



Non -pathogenic for mice; effect on other 

 animals not recorded. 



Anaerobic. Grows at 25 to 30 mm mercury 

 pressure. 



Optimum temperature, between 37° and 

 42° C. 



Optimum reaction, between pH 7.0 and 

 7.4. Grows between pH 6.0 and 8.4. 



Distinctive characters: Ability to liquefy 

 gelatin (with asparagine added), to coagu- 

 late milk, producing an orange sediment, 

 and to grow in media containing asparagine 

 without requiring the presence of cellulose. 



Spores resist heating at 100° C. for 90 min- 

 utes. 



Comments: This species was apparently 

 first isolated and studied in pure culture by 

 Clausen {op. cit., 1931, 40 and 54). From his 

 studies he concluded that Omeliansky's 

 Wasserstoffbacillus and Methanbacillus are 

 but a single species and that the gaseous 

 fermentation products are H2 and CO2 , not 

 methane; the production of methane ob- 

 served by Omeliansky was effected by the 

 symbiotic forms or other contaminants al- 

 ways present in Omeliansky's cultures. 

 Clausen's evidence is quite convincing, and 

 the organism is presented here from his de- 

 scription. 



Source: Isolated from human, cow and 

 horse excreta, from the stomach contents of 

 cows, from cheese and from soil. 



Habitat: Found in the intestinal canals 

 of animals and presumably thence widely 

 disseminated in soil. 



86. Clostridium dissolvens Bergey et 

 al., 1925. (Bacillus cellulosae dissolvens 

 Khouvine, Ann. Inst. Past., 87, 1923, 711; 

 Bergey et al.. Manual, 2nd ed., 1925, 344.) 



dis.sol'vens. L. part. adj. dissolvens dis- 

 solving. 



Slender rods, ranging from 2.5 to 12.5 mi- 

 crons in length, occurring singly and oc- 

 casionally in pairs, but not in chains. Spores 

 ovoid, terminal, swelling the cells. Non- 

 motile. Gram-negative. 



Cellulose is digested by the formation of 

 an endocellulase which acts only when the 

 bacteria are attached to the cellulose. Sac- 

 charides and CO2 , Ho , ethyl alcohol and 

 acetic, lactic and butyric acids are pro- 

 duced from cellulose. 



A yellow pigment is produced in the pres- 

 ence of cellulose. 



Glucose and carbohydrates other than 

 cellulose not fermented. 



Anaerobic. 



Grows between 35° and 51° C. without a 

 definite optimum. For the thermophilic 

 strain of Khouvine, see Clostridium thermo- 

 cellum Viljoen et al. 



Not pathogenic for guinea pigs. 



Distinctive character: Grows only in me- 

 dia containing cellulose, in the presence of 

 which it produces a yellow pigment. 



