■FAMILY p:xtp:koba(teriaceae 



445 



Wheeler, Jour. Bact., 4^. 1944. 357.) Named for Theodor Escherich, who first iso- 

 lated the type species. 



Short rods fermenting glucose and lactose with acid and gas production. Acetyl- 

 methylcarbinol is not produced. Methyl red test positive. Carbon dioxide and 

 hydrogen produced in approximately equal volumes from glucose. Generally not 

 able to utilize uric acid as a sole source of nitrogen. Found in feces and is occasionally 

 pathogenic to man (colitis, cystitis, etc.). It is, however, also widely distributed in 

 nature . 



The type species is Escherichia coli (Migula) Castellani and Chalmers. 



Key to the species of genus Escherichia. 



I. Citric acid and salts of citric acid not utilized as sole source of carbon. 

 A. Hydrogen sulfide not produced. 



1. Escherichia coli. 

 II. Citric acid and salts of citric acid utilized as sole source of carbon. 



A. Hydrogen sulfide produced. 



2. Escherichia freundii, 



B. Hydrogen sulfide not produced. 



3. Escherichia intermedium. 



1. Escherichia coli (Migula) Castellani 

 and Chalmers. {Bacterium coli com- 

 viune Escherich, Die Darmbakterien des 

 Neugeborenen und Sauglings, 1885; Ba- 

 cillus escherichii Trevisan, I generi e le 

 specie delle Batteriacee, 1889, 15 ; Bacillus 

 coli communis Sternberg, Manual of 

 Bacteriology, 1893, 439; Bacillus coli 

 Migula, in Engler and Prantl, Xattir- 

 lichen Pflanzenfam., /, la, 1895, 27; 

 Bacterium coli Lehmann and Xeumann, 

 Bakt. Diag., 1 Aufi., 2, 1896, 224; Bacillus 

 coli verus Durham, Jour. Exp. Med., 5, 

 1900, 371; Bacillus coli communis verus 

 Durham, ibid., 353; Aerobacter coli 

 Beijerinck, Cent. f. Bakt., II Abt., 6, 

 1900, 193; Castellani and Chalmers, Man. 

 Trop. Med., 3rd ed., 1919, 941; Bacillus 

 coli-communis Winslow, Kligler and 

 Rothberg, Jour. Bact., 4, 1919, 483; 

 Bacterium coli-communis Holland, Jour. 

 Bact., 5, 1920, 217; Colobactrum coli 

 Borman, Stuart and Wheeler, Jour. Bact., 

 48, 1944, 358.) From Latin colon, the 

 large intestine. 



Note: Weldin (Iowa State Jour. Sci., 

 1, 1927, 121) considers the following 

 identical with the above : Bacillus cavi- 

 cida Fliigge, Die Mikroorganismen, 1886, 

 268 or more probably Brieger, Berlin. 



klin. Wochnschr., 1884, No. 14; Bacillus 

 C, Booker, Trans. Ninth Internat. Med. 

 Congress, 3, 1887, 598; Bacillus schafferi 

 von Freudenreich, Landw. Jahrb. d. 

 Schweiz, 4, 1890, 17; Bacterium cavicida 

 Chester, Ann. Rept. Del. Col. Agr. Exp. 

 Sta., 9, 1897, 130; Bacterium schafferi 

 Chester, ibid., 74; Bacillus mustelae 

 septicus Matzuschita, Bakt. Diag., 1902; 

 Bacillus communis Jackson, Jour. Inf. 

 Dis., 8, 1911, 241 ; not Bacillus communis 

 Migula, Syst. d. Bakt., 2, 1900, 725; 

 Escherichia cavicida Castellani and Chal- 

 mers, Manual of Trop. Med., 3rd ed., 

 1919, 942; Escherichia schaefferi Bergey 

 et al., :VIanual, 1st ed., 1923, 196. 



Oesterle (Cent. f. Bakt., I Abt., Orig., 

 134, 1935, 115) has described a yellow 

 strain Bacterium coli flavum, Parr (Proc. 

 Soc. Exp. Biol, and Med., 35, 1937, 563) a 

 golden-brown strain Bacterium aurescens 

 (not Bacterium aurescens Migula, Syst. 

 d. Bakt., ^, 1900, 466), and Tittsler (Jour. 

 Bact., 33, 1937, 450) reddish-orange 

 strains which are regarded as pigmented 

 variants of Escherichia coli. 



Rods : Usually 0.5 by 1.0 to 3.0 microns, 

 varying from almost coccoid forms to long 

 rods, occurring singly, in pairs and short 

 chains. Motile or non-motile. Motile 



