FAMILY LACTOBACTERIACEAE 



353 



mass. Deep colonies, small, irregularly 

 shaped, with fine radiate or ramified 

 projections. 



Wort-agar slants : Growth scanty, 

 limited, dry, veil-like. 



Wort -broth : After 48 hours, fine, floccu- 

 lent sediment- Other acid broths sedi- 

 ment whitish, slight turbidity. 



Milk: Slow growth with small inocu- 

 lum. Coagulates from the bottom up 



Potato: No growth. 



Acid but no gas from glucose, sucrose 

 and lactose (Moro). Acid from glucose, 

 fructose, galactose, mannose, maltose, 

 lactose and sucrose. Some cultures 

 ferment raffinose and trehalose and have 

 slight action on dextrin. Xylose, arabi- 

 nose, rhamnose, glycerol, mannitol 

 .sorbitol, dulcitol and inositol not fer- 

 mented (Kulp and Rettgerj. Inactive 

 lactic acid and volatile acids formed from 

 sugars (Curran, Roger.s and Whittier). 



No visible growth in carbohydrate -free 

 media (Rettger, Levy, Weinstein and 

 Weiss) . 



Optimum temperature 37°C. No 

 growth at 20° to 22°C (Moro). Maximum 

 temperature 43° to48°C (Curran, Rogers 

 and Whittier). 



Not pathogenic for laboratory animal.>^. 



Microaerophilic . 



Distinctive characters : Grows in acid 

 media. Unless frequent transfers are 

 made, organism may become Gram-nega- 

 tive and rapidly develop characteristic 

 degeneration forms (Moro). The so- 

 called original strains of Bacillu-s <ici- 

 dophilus from the Krdl collection, do- 

 scribed and called Microbacteriiini 

 lacticum by Orla- Jensen, do not have the. 

 characteristics given by Moro. 



Source : From the feces of milk-fed 

 infants. Also from the feces of older 

 persons on high milk or lactose or dextrin- 

 containing diets. 



Habitat : As for source. 



5. Lactobacillus bifidus (Tissier) Hol- 

 land. (Bacillus bifiduis communis and 

 Bacillus bifidus Tissier, Recherches sur 

 la flore intestinal des nourrissons, Paris, 



1900, 85; Bacteroides bifidus Castellani 

 and Chalmers, Man. Trop. Med., 3rd ed., 

 1919, 960; Holland, Jour. Bact., 5, 1920, 

 223; Nocardia bifida Vuillemin, Encyclo- 

 pedic Mycolog., Paris, 3, Champignons 

 Parasites, 1931, 132; Actinomyces bifidus 

 Nannizzi, in PoUacci, Trat. Micopat- 

 Umana, 4, 1934, 13: Cohnistreptothrix 

 bifidus Negroni and Fisher, Rev. Soc. 

 Argentina Biol., 80, 1944, 315.) From 

 Latin bifidus split in two, cleft. 



Possible synonyms : Coccobacillus ovi- 

 formis Tissier, Ann. Inst. Past., 22, 1908, 

 189 (Bacterium ovi forme Le Blaye and 

 Guggenheim, Manual pratique de diag- 

 nostique Bact^riologie, Paris, 1914; Bac- 

 teroides oriformis Levine and Soppeland, 

 Iowa Engineering Exp. Sta. Bui. 77, 1926, 

 35) ; Bacillus ventriosus Tissier, loc. cit. 

 ^ Bacteroides ventriosris Eggerth, Jour. 

 Bact., 30, 1935, 281); Diplobacillus 

 acuminatus Distaso, loc. cit. (Bacteroides 

 acum inatus Rergey et al . , Manual , 1 st ed . , 

 1923, 260). 



Description supplemented from Weiss 

 and Rettger. Jour. Bact., 28, 1934, 501. 



Small, slender rods : Average length 4.0 

 microns, 0.5 lo 0.7 by 2 to 8 microns 

 (Weiss and Rettger), occurring singly or 

 in pairs and short chains, parallel to each 

 other, very variable in appearance. 

 Branched and club forms develop in some 

 cultures. Non-motile. Gram-positive 

 but stains irregularly in old cultures 

 (Tissier). 



Little or no growth in carbohydrate-free 

 agar (Weiss and Rettger) . 



Deep sugar-agar colonies : After 3 days, 

 solid with sligiitly irregular edge, whitish, 

 (irow up to 3 cm from the surface forming 

 ,•1 ling. Average diameter 3 mm. No 

 gas. 



Sugar broth: (iood growth. Turbid 

 within 3 days. Clears with fiocculent 

 precipitate. 



Milk : Gootl growth with large inocu- 

 lum. No coagulation (Tissier). Mayor 

 may n<jt coagulate milk (Weiss and 

 Rettger). 



Acid but no gas from glucose (Tissier). 

 Acid from glucose, fructose, galactose, 



