336 



ORDER IV. EUBACTERIALES 



1. Escherichia coli (Migula, 1895) 

 Castellani and Chalmers, 1919. {Bacterium 

 coli commune Escherich, Fortschr. d. Med., 

 3, 1885, 518; Bacillus escherichii Trevisan, 

 I generi e le specie delle Batteriacee, 1889, 

 15; Bacillus coli Migula, in Engler and 

 Prantl, Naturlich. Pflanzenfam., 1, la, 1895, 

 27; Bacterium coli Lehmann and Neumann, 

 Bakt. Diag., 1 Aufl., ^, 1896, 224; Castellani 

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

 1919, 941.) 



co'li. Gr. noun colum or colon the large 

 intestine, colon; L. gen. noun coli of the 

 colon. 



Rods, usually 0.5 by 1.0 to 3.0 microns, 

 varjing from almost coccoid forms to long 

 rods, occurring singly, in pairs and in short 

 chains. Motile or non-motile; motile strains 

 possess peritrichous flagella. Usually not 

 encapsulated. Non-spore-forming. Gram- 

 negative. 



Gelatin colonies: Opaque, moist, grayish 

 white, entire. 



Gelatin stab: Grayish white, spreading, 

 undulate growth. No liquefaction. 



Agar colonies: Usually white, sometimes 

 yellowish white, entire to undulate, moist, 

 homogeneous. Atypical forms occur fre- 

 quently. 



Agar slant: Usually white, sometimes 

 yellowish white, moist, glistening, spread- 

 ing growth. 



Broth: Turbid; heavy, grayish sediment; 

 no pellicle. 



Litmus milk: Rapid acid production with 

 development of gas; usually coagulated; 

 curd may or may not be broken up; no 

 peptonization of the curd. Litmus may or 

 may not be reduced. 



Potato: Abundant, grayish to yellowish, 

 spreading growth. 



Blood agar plates: Different strains vary 

 widely in their action, some being hemoly- 

 tic (Buchgraber and Hilko, Zent. f. Bakt., 

 I Abt., Orig., 133, 1935, 449). 



Indole usually produced. 



No hydrogen sulfide produced in peptone 

 iron agar (Levine, Epstein and Vaughn, 

 Amer. Jour. Public Health., 24, 1934, 505; 

 Tittsler and Sandholzer, Amer. Jour. Public 

 Health, 27, 1937, 1240). More sensitive 

 indicators give positive tests for hydrogen 



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

 1938, 20). 



Methjd red test positive (Clark and Lubs, 

 Jour. Inf. Dis., 17, 1915, 160); Voges-Pro- 

 skauer test negative (Durham, Jour. Exp. 

 Med., 5, 1901, 373); inverse correlation be- 

 tween methyl red and Voges-Proskauer 

 tests (Levine, Jour. Bact., 1, 1916, 153). 



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 fermented. Cellobiose (Jones 

 and Wise, Jour. Bact., 11, 1926, 359) and 

 a-methyl-glucoside (Koser and Saunders, 

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

 See Twort (Proc. Royal Soc. London, 79, 

 1907, 329) for utilization of unusual gluco- 

 sides, Dozois et al. (Jour. Bact., 30, 1935, 

 189; and 32, 1936, 499) for utilization of 

 certain sugar alcohols and their anhydrides, 

 and Poe and Klemme (Jour. Biol. Chem., 

 109, 1935, 43) for utilization of rare sugars. 

 See Winslow, Kligler and Rothberg (Jour. 

 Bact., 4, 1919, 429) for review of literature 

 relative to classification. 



Gas ratio: Approximately equal volumes 

 of carbon dioxide and hydrogen, ratio 

 1:1, are produced from glucose (Harden and 

 Walpole, Proc. Roy. Soc, Ser. B, 77, 1905, 

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

 Dis., 14, 1914, 411). 



Trimethyleneglycol not produced from 

 glycerol by anaerobic fermentation (Braak, 

 Onderzoekingen over Vergisting van Glyc- 

 erine. Thesis, Delft, 1928, 166; Werkman 

 and Gillen, Jour. Bact., 23, 1932, 167). 



Citric acid and salts of citric acid not 

 utilized as sole sources of carbon (Koser, 

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



Nitrites produced from nitrates. 



Uric acid not utilized as a sole source of 

 nitrogen (Koser, Jour. Inf. Dis., 23, 1918, 

 377) ; uracil utilized as a sole source of 

 nitrogen (Mitchell and Levine, Jour. Bact., 

 35, 1938, 19). 



Fecal odor produced. 



