FAMILY IV. ENTEROBACTERIACEAE 



343 



Growth requirements: Good growth on 

 ordinary laboratory media. Optimum tem- 

 perature, about 30° C. Grows better at 

 temperatures below 30° C. than does Esch- 

 erichia coli Castellani and Chalmers. 

 Usually destroyed in 30 minutes at 60° C, 

 but certain heat-resistant strains may with- 

 stand this exposure (Avers and Johnson, 

 Jour. Agr. Res., S, 1914, 401; Stark and 

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

 Gas not produced in Eijkmann test when 

 carried out at 45° to 46° C. (Eijkmann, 

 Cent. f. Bakt., I Abt., Orig., 37, 1904, 74; 

 Levine, Epstein and Vaughn, Amer. Jour. 

 Pub. Health, 24, 1934, 505). 



Comments: Thompson (Jour. Bact., S8, 

 1934, 41) has reported a variety of this 

 organism which shows a transverse arrange- 

 ment of the capsule. 



Relationships to other species: Regarded 

 by Escherich {op. cit., 1885, 520) as possibly 

 identical with Hueppe's Milchsiiurebac- 

 terium (Mit. d. kais. Gesund., 2, 1884, 340; 

 Escherichia coli var. acidilactici) . However, 

 because he did not have a culture of 

 Hueppe's organism for comparison, Esch- 

 erich gave the name Bakterium lactis aero- 

 genes to his own organism. 



Source: Isolated from the feces of breast- 

 fed infants. 



Habitat: Normally found on grains and 

 plants and, to a varying degree, in water, 

 milk, dairy products and the intestinal 

 canals of man and other animals. Widely 

 distributed in nature. 



2. Aerobacter cloacae (Jordon, 1890) 

 Bergey et al., 1923. (Bacillus cloacae Jordan, 

 Rept. Mass. State Bd. of Health, Part II, 

 1890, 836; also see Jordan, Jour. Hyg., 3, 

 1903, 1; Bacterium cloacae Lehmann and 

 Neumann, Bakt. Diag., 1 Aufl., 2, 1896, 

 239; Bergey et al., Manual, 1st ed., 1923, 

 207.) 



clo.a'cae. L. noun cloaca a sewer; L. 

 gen. noun cloacae of a sewer. 



Rods, 0.5 to 1.0 by 1.0 to 2.0 microns, 

 occurring singly. Usually motile by means 

 of peritrichous flagella. Not encapsulated. 

 Gram-negative. 



Gelatin colonies: Thin, circular, bluish, 

 translucent. 



Gelatin stab: Slow liquefaction. Liquefy- 



ing power sometimes lost (Kligler, Jour. 

 Inf. Dis., 15, 1914, 199). 



Agar colonies: Circular, thick, opaque 

 with white center, entire. 



Agar slant: Porcelain-white, smooth, 

 glistening, spreading growth. 



Broth: Turbid; thin pellicle. 



Litmus milk: Acid; coagulation; gas; 

 slow peptonization. 



Potato: Yellowish, moist, glistening 

 growth. 



Indole not produced (Levine, Epstein and 

 Vaughn, Amer. Jour. Pub. Health, 24, 1934, 

 505; Wilson, Med. Res. Council, London, 

 Spec. Rept. Ser. 206, 1935, 161). 



Hydrogen sulfide not produced in pep- 

 tone iron agar (Levine, Epstein and 

 Vaughn, op. cit., 1934, 505). 



Acid and gas from glucose, fructose, 

 galactose, arabinose, xylose, lactose, mal- 

 tose, raffinose, dextrin, salicin, trehalose, 

 mannitol, sorbitol, cellobiose anda-methyl- 

 glucoside. Sucrose usually fermented. 

 Inulin, esculin, starch, dulcitol, rhamnose 

 and protopectin not attacked. Glj'cerol 

 fermented with no visible gas (Kligler, 

 op. cit., 1914, 187; Levine, Amer. Jour. Pub. 

 Health, 7, 1917, 784). Starch rarely fer- 

 mented (Levine, loc. cit.). See Winslow, 

 Kligler and Rothberg (Jour. Bact., 4, 1919, 

 429) for a review of the literature. 



Gas ratio: Glucose fermented with at 

 least two volumes of carbon dioxide to one 

 of hydrogen (Rogers, Clark and Davis, 

 Jour. Inf. Dis., 74, 1914,411). 



Methyl red test negative; Voges-Pro- 

 skauer test positive. 



Citric acid and salts of citric acid may be 

 utilized as sole sources of carbon (Koser, 

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



Uric acid may be utilized as a sole source 

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

 377). 



Sodium hippurate not hj^drolj^zed (Hajna 

 and Damon, Amer. Jour. Hyg., 19, 1934, 

 545) . 



Nitrites produced from nitrates. 



Fecal odor produced. 



Catalase-positive. 



Aerobic, facultatively anaerobic. 



Growth requirements: Good growth on 

 ordinary laboratory media. Optimum tem- 

 perature, between 30° and 37° C. Gas not 



