FAMILY X. LACTOBACILLACEAE 



521 



Spheres, occurring in moderately long 

 chains. Some cultures show very long 

 chains in broth. 



Serology: No group-specific antigen has 

 been demonstrated. 



Action on blood: Usually weak greening. 

 No soluble hemolysin produced. 



Temperature relations : Growth at 45° but 

 not at 50° C. No growth at 10° C. Occa- 

 sional strains survive 60° C. for 30 minutes. 



Tolerance tests: Growth in broth con- 

 taining 2 per cent NaCl but not in 6.5 per 

 cent NaCl. No growth at pH 9.6 or in milk 

 containing 0.1 per cent methjdene blue. 

 Growth on 40 per cent bile blood agar. 



Litmus milk: No visible change. 



Final pH in glucose broth, between 4.0 

 and 4.5. 



No polysaccharide synthesized from 

 sucrose. 



Acid from glucose, fructose, galactose, 

 maltose and usually from sucrose and 

 salicin. Raffinose and inulin are seldom fer- 

 mented. No acid from arabinose, xylose, 

 lactose, mannitol or glycerol. 



Starch is hydrolyzed on a favorable me- 

 dium. Sodium hippurate and gelatin not 

 hydrolj-zed. Esculin split. 



Ammonia not produced from arginine. 



Distinctive character: This species is 

 ordinarily differentiated from the other 

 viridans streptococci by its inability to fer- 

 ment lactose. However, occasional strains 

 in other species of this group also fail to 

 ferment this sugar, thus necessitating the 

 determination of the tolerance to bile, of 

 the ability to hydrolyze starch and of other 

 tests for final identification. 



Source and habitat: Predominating strep- 

 tococcus in the alimentarj- tract of the 

 horse. 



14. Streptococcus therniophilus Orla- 

 Jensen, 1916. (Maelkeri-Bacteriologi, 1916, 

 37; The Lactic Acid Bacteria, 1919, 136.) 



ther.mo'phil.us. Gr. noun therme heat; 

 Gr. adj. philus dear, loving; M.L. adj. 

 therniophilus heat-loving. 



Spherical or ovoid cells, 0.7 to 0.9 micron 

 in diameter, occurring in pairs to long 

 chains. Gram-positive. 



Serology: No group-specific antigen has 

 been demonstrated. 



Action on blood: Most strains produce a 

 weak greening reaction. 



Temperature relations: Optimum, be- 

 tween 40° and 45° C. Grows at 50° but not 

 at 53° C. No growth below 20° C. Survives 

 65° C. for 30 minutes. 



Tolerance tests: Very sensitive to salt as 

 indicated by no growth in broth containing 

 2 per cent NaCl. No growth in milk con- 

 taining 0.01 per cent methylene blue nor on 

 10 per cent bile blood agar. 



Litmus milk: Acid, curdled, followed by 

 reduction of the litmus. No digestion. 



Final pH in glucose broth, between 4.0 

 and 4.5. Members of this species preferen- 

 tially ferment the disaccharides sucrose and 

 lactose and, therefore, may show a lower 

 final pH from fermenting these sugars than 

 from fermenting glucose. 



No polysaccharide is synthesized from 

 sucrose. 



Acid from glucose, fructose, lactose and 

 sucrose; seldom ferments the pentoses or 

 raffinose. No acid from trehalose, maltose, 

 inulin, glycerol, mannitol, sorbitol or sali- 

 cin. 



Starch may be hydrolyzed on a favorable 

 medium. Sodium hippurate and gelatin not 

 hjfdrolyzed. Esculin not split. 



Ammonia not produced from arginine. 



Distinctive characters: This species may 

 be easily recognized by its high tempera- 

 ture range for growth, its thermal tolerance, 

 its extreme sensitivity to salt and its in- 

 ability to ferment maltose. 



Source: Milk and milk products. Em- 

 ployed as a starter for Swiss cheese. 



Habitat: Unknown. 



15. Streptococcus uberis Diernhofer, 

 1932. (Diernhofer, Milchw. Forsch., IS, 

 1932, 368; "Group III" non-hemolytic 

 streptococci, Edwards, Jour. Comp. Path. 

 Therap., 45, 1932, 43.) 



u'ber.is. L. noun uber udder, teat; L. 

 gen. noun uberis of an udder. 



Description taken from Seeley (Jour. 

 Bact., 6S, 1951, 107). 



Spheres, occurring in pairs or chains of 

 moderate length. 



Serolog}-: A group-specific and distinctive 

 antigen has been reported to exist among the 

 strains tested (Seeley, loc. cit.), but the sta- 



