446 



MANUAL OF DETERMINATIVE BACTERIOLOGY 



strains have peritrichous flagella. Not 

 usually capsulated. Non-spore-forming. 

 Gram-negative. 



Gelatin colonies: Opaque, moist, gray- 

 ish-white, entire. 



Gelatin stab: Grayish-white, spread- 

 ing, undulate. No liquefaction. 



Agar colonies: Usually white, some- 

 times yellowish-white, rarely yellow, 

 yellow-brown, golden-brown, reddish- 

 orange or red; entire to undulate, moist, 

 homogeneous. Atypical forms occur fre- 

 quently. 



Agar slant: Usually white, sometimes 

 yellowish-white, rarely yellow, yellow- 

 brown, golden-brown, reddish-orange or 

 red growth; moist, glistening, spreading. 



Broth: Turbid, with heavy grayish 

 sediment. No pellicle. 



Litmus milk: Rapid acid formation 

 with development of gas, usually coagula- 

 tion, curd may or may not be broken up, 

 no peptonization of the curd. Litmus 

 may or may not be reduced. 



Potato: Abundant, grayish to yellow- 

 ish-brown, spreading. 



Indole usually formed. 



Nitrites produced from nitrates. 



Blood agar plates: Different strains 

 vary widely in their action, some being 

 hemolytic (Buchgraber and Hilk6, Cent, 

 f. Bakt., I Abt., Grig., 1S3, 1935, 449). 



Heat resistance : Usually destroyed in 

 30 minutes at 60°C, but certain heat- 

 resistant strains may withstand this 

 exposure (Ayers and Johnson, Jour. Agr. 

 Res., 3, 1914, 401; Stark and Patterson, 

 Jour. Dairy Sci., 19, 1936, 495). 



Antigenic structure : An antigenically 

 heterogeneous species. 



Methyl red test positive (Clark and 

 Lubs, Jour. Inf. Dis., 17, 1915, 160); 

 Voges-Proskauer test negative (Durham, 

 Jour. Exp. Med., 5, 1901, 373); inverse 

 correlation between methyl red and 

 Voges-Proskauer tests (Levine, Jour. 

 Bact., 1, 1916, 153). 



Citric acid and salts of citric acid not 

 utilized as sole source of carbon (Koser, 

 Jour. Bact., 8, 1923, 493). 



Uric acid not utilized as sole source of 



nitrogen (Koser, Jour. Inf. Dis., 28, 1918, 

 377) ; uracil utilized as sole source of 

 nitrogen (Mitchell and Levine, Jour. 

 Bact., 35, 1938, 19). 



Gas ratio : Approximately equal vol- 

 umes of carbon dioxide and hydrogen, 

 ratio 1:1, produced from glucose (Harden 

 and Walpole, Proc. Roy. Soc, Ser. B, 77, 

 1905, 399; Rogers, Clark and Davis, Jour. 

 Inf. Dis., 14, 1914, 411). 



Catalase produced. 



No H2S produced in peptone iron agar 

 (Levine, Epstein and Vaughn, Amer. 

 Jour. Public Health, 24, 1934, 505; Titts- 

 ler and Sandholzer, Amer. Jour. Public 

 Health, 27, 1937, 1240). More sensitive 

 indicators give positive tests for H2S 

 (Hunter and Weiss, Jour. Bact., 35, 1938, 

 20). 



Trimethyleneglycol not produced from 

 glycerol by anaerobic fermentation 

 (Braak, Onderzoekingen over Vergisting 

 van Glycerine, Thesis, Delft, 1928, 166; 

 Werkman and Gillen , Jour. Bact., 23, 

 1932, 167). 



Acid and gas from glucose, fructose, 

 galactose, lactose, maltose, arabinose, 

 xylose, rhamnose and mannitol. Sucrose, 

 raffinose, salicin, esculin, dulcitol and 

 glycerol may or may not be fermented. 

 Variable fermentation of sucrose and 

 salicin (Sherman and Wing, Jour. Bact., 

 33, 1937, 315; Tregoning and Poe, Jour. 

 Bact., 34, 1937, 473) . Inulin, pectin and 

 adonitol rarely fermented. Dextrin, 



starch, glycogen and inositol not fer- 

 mented. Cellobiose (Jones and Wise, 

 Jour. Bact., 11, 1926, 359) and a-methyl- 

 glucoside (Koser and Saunders, Jour. 

 Bact., 24, 1932, 267) not fermented. 

 Certain strains produce variants which 

 ferment lactose slowly or not at all (Ren- 

 nebaum, Jour. Bact., 30, 1935, 625). 

 Some strains of slow-lactose-fermenters 

 appear to be intermediate between the 

 coliform and paratyphoid groups (Sandi- 

 ford, Jour. Path, and Bact., 4I) 1935, 

 77). See Twort (Proc. Royal Soc. Lon- 

 don, 79, 1907, 329) for utilization of 

 unusual glucosides; Dozois et al. (Jour. 

 Bact., 30, 1935, 189 and 32, 1936, 499) 



