FAMILY X, LACTOBACILLACEAE 



539 



No toxin and no hemolysin. 



Distinctive characters: Strongly acidifies 

 media; coagulates milk. 



Source: Isolated from lochia and uterus 

 in puerperal sepsis; also from cases of gan- 

 grene of the lung, pleurisy, bronchiectasis 

 and appendicitis. 



Habitat : Found in the human respiratory 

 and digestive tracts and in the vagina. 



9. Peptostreptococcus evolutus (Pre- 

 vot, 1924) Smith, comb. nov. (Streptococcus 

 Sch. (Schwarzenbek), Graf and Wittneben, 

 Cent. f. Bakt., I Abt., Orig., U, 1907, 97; 

 Streptococcus evolutus Pr6vot, Thes. M6d., 

 Paris, 1924; Streptococcus Schwarzenbeck 

 (sic) Ford, Textb. of Bact., 1927, 455: also 

 see Weiss and Mercado, Jour. Inf. Dis., 

 62, 1938, 181.) 



e.vo.lu'tus. L. part. adj. evolutus unrolled. 



Description taken in part from Prevot 

 (Ann. Sci. Nat., Ser. Bot., 15, 1933, 199). 



Spheres, 0.7 to 1.0 micron in diameter, 

 averaging 0.7 micron, occurring in pairs 

 or in short and long chains. Pleomorphic. 

 Often appear as short, ovoid rods with 

 rounded ends. Gram-positive. 



Gelatin: Liquefaction. 



Deep agar colonies : Lenticular or rosettes. 

 Growth occurs about one cm beneath the 

 surface; after a transfer the second gen- 

 eration may show a ring of growth in the 

 middle of this sterile zone . This is the charac- 

 teristic alternate zones appearance. Suc- 

 cessive generations may grow fully when 

 exposed to the air. Colonies usually become 

 brownish with age. 



Glucose broth: Abundant growth resem- 

 bling bread crumbs. Medium strongly 

 acidified (pH 5). A small quantity of lactic 

 acid is produced. 



Peptone broth: Rapid growth; no general 

 turbidity; precipitating, flocculent growth 

 on the wall of the tube; indole not pro- 

 duced. 



Blood agar: No change, sometimes green- 

 ing. 



Litmus milk: Acid; curdled in 24 hours; 

 clot retracts and fragments; slight peptoni- 

 zation with some strains. 



Coagulated protein not attacked. 



Acid from glucose, fructose, galactose. 



sucrose, lactose and maltose. Arabinose 

 sometimes fermented. 



Anaerobic, becoming aerotolerant with 

 subsequent transfers. Viability is short 

 aerobically and several months anaerobi- 

 cally. 



Optimum temperature, between 36° and 

 38° C. No growth below 22° C. 



Optimum pH, between 6.0 and 8.5. 



Pathogenicity: Most strains are not 

 pathogenic; some produce slight local swell- 

 ing subcutaneously with little pus in 

 guinea pigs and mice. 



Distinctive characters: Growth in alter- 

 nate zones in agar; strict anaerobe at first, 

 later aerotolerant. 



Source: Isolated from skin abscesses and 

 from cases of appendicitis, synergistic 

 gangrene and endocarditis. 



Habitat: Found in the respiratory tract, 

 mouth and vagina. 



10. Peptostreptococcus magnus (Pre- 

 vot, 1933) Smith, comb. nov. (Diplococcus 

 magnus anaerobius Tissier and Martelly, 

 Ann. Inst. Past., 16, 1902, 885; Diplococcus 

 magnus Prevot, Ann. Sci. Nat., Ser. Bot., 

 15, 1933, 140.) 



mag'nus. L. adj. magnus large. 



Large spheres, 1.5 to 1.8 microns in di- 

 ameter, usually in pairs, sometimes occur- 

 ring singly, in small clumps or in very short 

 chains. Gram-positive. 



Gelatin: Growth slow, scant. No lique- 

 faction. 



Deep agar colonies: After 24 hours at 

 37° C, lenticular, whitish, granular; margin 

 finely cut. No gas produced. 



Broth: Turbid, clearing in 4 or 5 days 

 resulting in a viscous mass similar to the 

 zoogloea which Clostridium bifermentans 

 forms . 



Peptone broth: Slight turbidity; indole 

 not produced. 



Milk: Unchanged. 



Carbohydrates not attacked. 



Fibrin not digested. 



Sterilized urine : Turbid in 3 to 4 days. The 

 urea is attacked forming (NH4)2C03. 



Proteoses: Digested and disintegrated 

 forming (NH4)2C03 with the liberation of 

 NH3. 



Anaerobic. 



