FAMILY XIII. BACILLACEAE 



621 



Tyrosine agar slants: Growth same as on 

 agar. 



Broth: Clear with heavy, wrinkled, waxy, 

 tough pellicle. Variations: Flocculent or 

 uniform turbidity with or without fragile 

 pellicle. 



NaCl broth: Good growth up to a con- 

 centration of 7 per cent NaCl; growth in a 

 few cases in 10 or 12 per cent. 



Milk: Slowly peptonized, usually be- 

 coming alkaline. 



Milk agar streak plate : Usuallj^ there is a 

 wide zone of hydrolysis of the casein. 



Potato: Growth heavy, wrinkled to 

 coarsely folded, spreading. Offwhite, yellow, 

 pink or brown. Variations: Slimy, soft, 

 thin, warty. 



Acid but no gas (with ammonium salts as 

 source of nitrogen) from arabinose, xylose, 

 glucose, sucrose and mannitol. Usually no 

 acid produced from lactose. 



Starch is hydrolyzed. 



Acetylmethj'lcarbinol produced (37° C. 

 better incubation temperature than 32° C). 



pH of glucose broth cultures is 5.0 to 8.6 

 in 7 days. 



Citrates utilized. 



Nitrites produced from nitrates. No gas 

 produced from nitrate broth under ana- 

 erobic conditions. 



Aerobic, certain strains facultatively 

 anaerobic. Growth scant, if any, in glucose 

 broth under anaerobic conditions; pH of 

 14-day cultures is 5.5 or higher. 



Temperature relations: Optimum growth 

 temperatures lie between 28° and 40° C. 

 The maximum temperature for growth is 

 usually 50° C, but some cultures find 40° 

 too warm for growth while still others will 

 grow even up to 55° C. 



Accessory growth factors not essential. 



Lecithinase not produced. 



Antibiotics obtained from cultures of 

 certain strains are subtilin (Jansen and 

 Hirschmann, Arch. Biochem., 4, 1944, 297), 

 bacillin (Foster and Woodruff, Jour. Bact., 

 51, 1945, 363), subtenolin (Hirschhorn, 

 Bucca and Thayer, Proc. Soc. Exp. Biol, and 

 Med., 67, 1948, 429), bacillomycin (Landy, 

 Warren, Rosenman and Colio, Proc. Soc. 

 Exp. Biol, and Med., 67, 1948, 539) and oth- 

 ers. 



Source: Isolated from infusions of lentils, 

 cheese, white beets and hay (Cohn). 



Habitat: Widely distributed in soil and 

 decomposing organic matter; also common 

 as a laboratory contaminant. 



6a. Bacillus subtilis var. aterrimus (Leh- 

 mann and Neumann, 1896) Smith et al., 

 1946. (Potato bacillus, Biel, Cent. f. Bakt., 

 II Abt., 2, 1896, 137; Bacillus aterrimus 

 Lehmann and Neumann, Bakt. Diag., 1 

 Aufl., £, 1896, 303; Smith, Gordon and Clark, 

 U. S. Dept. Agr. Misc. Pub. 559, 1946, 64.) 



a.ter'ri.mus. L. sup. adj. aterrimus very 

 black. 



The description of Bacillus subtilis will 

 serve for var. aterrimus with the additional 

 statement that a blue-black to black pig- 

 ment is formed on media containing a car- 

 bohydrate utilized by the organism. The 

 ability to form black pigments, however, 

 may be lost and the cultures stabilized in 

 the colorless condition (Smith et al., ibid., 

 9; also see op. cit., 1952, 29); they are then 

 indistinguishable from cultures of Bacillus 

 subtilis. 



Source: Isolated from rye bread in a 

 moist chamber used for growing aspergilli 

 (Biel). 



Habitat: Widely distributed in soil, air 

 and decomposing carbonaceous materials. 



6b. Bacillus stibtilis var. niger (Migula, 

 1900) Smith et al., 1946. (Bacillus laciis 

 niger Gorini, Gior. d. Reale Soc. Ital. d'Ig., 

 16, 1894, 9; also see Cent. f. Bakt., I Abt., 

 Orig., 20, 1896, 94; Bacillus niger IMigula, 

 System der Bakterien, 2, 1900, 636; Smith 

 et al., U. S. Dept. Agr. Misc. Pub. 559, 1946, 

 66.) 



ni'ger. L. adj. niger black. 



The characterization of Bacillus subtilis 

 will serve for var. niger by adding the state- 

 ment that media containing tyrosine are 

 blackened. The ability to form black pig- 

 ment, however, may be lost and the cultures 

 stabilized in the colorless condition; then 

 they cannot be distinguished from Bacillus 

 subtilis. 



Source: Isolated from milk. 



Habitat: Widely distributed in soil, dust 

 and decomposing materials. 



