FAMILY VI. BACTEROIDACEAE 



423 



Small, slender rods, 0.2 to 0.3 by 0.5 to 

 1.0 micron, with pointed ends. Capsules 

 formed are of much finer texture than those 

 surrounding Noguchia granulosis or No- 

 guchia simiae. IMotile by means of six to 

 eight peritrichous flagella. Not acid-fast. 

 Gram-negative. 



Gelatin agar colonies: Grayish, mucoid, 

 confluent. 



Gelatin stab: Tenuous, arborescent, non- 

 spreading growth. No liquefaction. 



Agar colonies: Small, spherical, translu- 

 cent, slightly grayish, smooth, somewhat 

 convex, moist, mucoid, entire. 



Agar slants: Slightly grayish, translu- 

 cent, coalescent, glistening, mucoid, homo- 

 geneous, non-spreading growth. The water of 

 sj'neresis appears uniformly cloudy or milky 

 depending on the amount of growth. 



Blood agar colonies: More profuse, more 

 grayish and less translucent than those on 

 plain agar. 



Leptospira medium: After 24 hours there 

 is a faint, nebulous surface growth followed 

 by an ingrowing sac-like mass, with its base 

 5 mm across, lying at the center of the 

 under surface and extending for 5 mm into 

 the medium. The area spreads laterally 

 until at about two or three days there is a 

 uniform, opaque, whitish layer about 1 cm 



thick which progresses slowly until the 

 bottom of the tube is reached in about seven 

 days. 



Broth: Uniformly turbid; no pellicle. 



Litmus milk: Unchanged. 



Potato: Faint, buff-colored (changing to 

 brown after five days), non-spreading, 

 sparse surface growth. 



Indole not produced. 



No acid or gas from glucose, fructose, 

 mannose, mannitol, sucrose, raffinose, 

 inulin, galactose, maltose, salicin, xylose, 

 dextrin, arabinose, amygdalin, lactose, 

 dulcitol, rhamnose, trehalose, sorbitol or 

 inositol. 



Nitrites not produced from nitrates. 



Aerobic, facultatively anaerobic. 



Temperature relations: Optimum, be- 

 tween 28° and 30° C. Thermal death point, 

 56° C. for 15 to 30 minutes. 



Serological reactions: Rabbit antiserum 

 is specific for all strains, and there is no 

 cross agglutination with Noguchia granulosis 

 or Noguchia simiae. 



Distinctive characters : No action on car- 

 bohydrates. Agglutination. 



Source: Isolated from spontaneous con- 

 junctival folliculosis, Type II, of rabbits. 



Habitat: Causes conjunctival folliculosis 

 in rabbits 



FAMILY VI. BACTEROIDACEAE BREED, MURRAY AND SMITH, Fam. Nov.^ 



Bac.te.ro.i.da'ce.ae. M.L. noun Bacteroides type genus of the family; -aceae ending to 

 denote a family; M.L. fem.pl.n. Bacieroidaceae the Bacteroides family. 



Rods, with rounded or pointed ends, w^hich vary in size from minute, filterable forms to 

 long, filamentous, branching forms; marked pleomorphism may occur. May be motile or 

 non-motile, the motile species possessing peritrichous flagella (rarely, motility has been 

 ob.served without demonstrable flagella). Gram-negative. Body fluids are frequentl}- re- 

 quired for growth and are always stimulative. Simple carbohydrates are usuall}' fermented 

 with the production of acid; gas may be produced in glucose or peptone media. Normally 

 these are strict anaerobes, but occasionally microaerophilic species occur. Found primarily 

 in the intestinal tracts and mucous membranes of warm-blooded animals. Sometimes patho- 

 genic. 



* Prof. Robert S. Breed, Cornell University, Geneva, New York, Prof. E. G. D. Murraj^ 

 University of Western Ontario, Canada, and Dr. Nathan R. Smith, Senior Bacteriologist, 

 Retired, Plant Industry Station, U. S. Department of Agriculture, Beltsville, Maryland, 

 have prepared the general sections for Family Bacieroidaceae, June, 1955. Other contribu- 

 tors as noted have prepared the sections covering special groups within this family. 



