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MANUAL OF DETERMINATIVE BACTERIOLOGY 



Agar stab: Heavy surface growth on 

 tryptone glucose extract agar at 21°C 

 with no growth along the line of inocu- 

 lation. 



Agar slant: On tryptone glucose ex- 

 tract agar at 21 °C after 2 days growth 

 abundant, glistening, filiform, non -viscid 

 and cream-colored. After extended in- 

 cubation the color usually is brown. 

 On special cheese agar in an atmosphere 

 of oxygen the growth is bright orange to 

 reddish-brown in 4 or 5 days. 



Broth: Turbidity and sediment. 



Potato : At 21°C after 5 days, growth is 

 scanty, smooth, glistening, and varies in 

 color from grayish to brownish -orange. 



Litmus milk: At 21°C the changes are 

 very slow. After 6 or 7 days the reac- 

 tion becomes alkaline and a yellow sedi- 

 ment appears. After approximately 10 

 days some digestion is evident, complete 

 digestion generally requiring several 

 weeks to over a month. A distinct am- 

 moniacal odor, more or less objection- 

 able, produced in old cultures. No 

 coagulation. Ropiness often produced 

 on extended incubation. 



Indole not produced. 



Nitrites produced from nitrates. 



Methyl red and Voges Proskauer reac- 

 tions negative. 



Hydrogen sulfide produced in broth 

 and on agar by some cultures but not 

 by others. 



Natural fats not hydrolyzed. 



No acid or gas from arabinose, dex- 

 trin, glucose, dulcitol, galactose, inulin, 

 lactose, fructose, maltose, mannitol, 

 raffinose, rhamnose, salicin, sorbitol, 

 sucrose or xylose. 



Ethyl, propyl, but3i and amyl alco- 

 hols o.xidized largely to corresponding 

 acids ; he.xyl and heptyl alcohols attacked 

 much less actively. 



Catalase rapidly produced in or on 

 various media. 



Aerobic. 



Growth temperatures: Growth at 8° 

 and 37°C but not at 45°C, with the opti- 

 mum at about 21 °C. 



Heat resistance low, cultures being 

 killed at 62.8°C in a few minutes. 



Growth in the pH range 6.0 to 9.8; no 

 growth at pH 5.0 or below. 



Salt tolerant, cultures growing readily 

 in a concentration of 15 per cent salt in 

 broth or skim milk, with certain cultures 

 apparently capable of growing somewhat 

 in much higher concentrations. 



Closely related to or identical with 

 Bacterium erythrogenes Lehmann and 

 Neumann. 



Source: Originally isolated by Wolff 

 from the surface flora of various soft 

 cheeses. 



Habitat: Widely distributed in and 

 especially on the surface of dairy prod- 

 ucts including blue, brick, camembert, 

 limburger, oka and cheddar cheeses, 

 butter, milk and cream. Also found in 

 various feeds including grains, silage, 

 green plants, hay and straw, and in 

 water, soil, manure, and air. 



4. Bacteriixm mycoides (Grotenfelt) 

 Migula. (Bacterium mycoides roseum 

 Grotenfelt, Fortschr. d. Med., 7, 1889, 

 46; Bacillus mycoides roseus Sternberg, 

 Manual of Bact., 1893, 640; Migula, 

 Syst. d. Bakt., 2, 1900, 482; Bacillus 

 mycoides-roseus Holland, Jour. Bact., 5, 

 1920, 219; Erythrohacillus mycoides- 

 roseus Holland, ibid.; Serratia rosea 

 Bergey et al.. Manual, 1st ed., 1923, 96; 

 Chromohacteriuvi mycoides roseum Top- 

 ley and Wilson, Princip. of Bact. and 

 Immun., ?, 1931, 402.) From Greek 

 mykes, fungus and eidos, form. 



Rods: Non -motile. Gram-positive. 



(ielatin colonies: Red, felt-like. 

 Liquefaction. 



Gelatin stab: Rapid liquefaction. 

 Red pellicle. Red sediment. 



Colonies composed of interlacing fila- 

 ments (Crookshank, Textb. of Bact. and 

 Inf. Dis., 1900, 524). 



.\gar stab: Red color produced if 

 grown in dark; a white color in presence 

 of light. 



