FAMILY IV. PSEUDOMONADACEAE 



117 



Source: Isolated from soil. 

 Habitat: Soil. 



48. Pseudomonas indoloxidans Gray, 

 1928. (Proc. Roy. Soc. London, B, 102, 1928, 

 263.) 



in.dol.o'xi.dans. M.L. neiit.n. indolum 

 indole; M.L. part. adj. oxidans oxidizing; 

 from Gr. adj. oxys sharp, acid; M.L. part, 

 adj. indoloxidans indole-oxidizing. 



Rods 1.0 by 3.0 microns. Motile with one 

 to four polar flagella. Gram-negative 



Gelatin colonies: Round, convex, buff, 

 smooth, glistening, erose. 



Gelatin stab: No liquefaction. 



Agar colonies: Round, convex, white, 

 watery; transparent border, erose. 



Agar slant: Filiform, convex, whitish, 

 smooth, glistening, undulate. 



Broth: Cloudy. 



Indole not produced. 



Nitrites produced from nitrates. No gas. 



No acid or gas from glucose, sucrose, lac- 

 tose, maltose or glycerol. 



Starch not hydrolyzed. 



Phenol and m-cresol not attacked. 



Distinctive character: Indole decomposed 

 in mineral salts agar medium with the for- 

 mation of blue crystals of indigotin. 



Aerobic. 



Optimum temperature, between 25° and 

 28° C. 



Source: Isolated from soil from Italian 

 Tyrol. 



Habitat: Soil. 



49. Pseudomonas niira McBeth, 1916. 

 (Soil Science, 1, 1916, 467.) 



mi'ra. L. adj. minis extraordinary. 



Rods 0.4 by 1.6 microns. Motile with a 

 single polar flagellum. Gram-negative. 



Gelatin stab: Good growth. No liquefac- 

 tion. 



Agar colonies : Circular, convex, grayish 

 white, granular, lacerate. 



Agar slant: Moderate, flat, grayish white, 

 somewhat iridescent. 



Broth: Turbid. 



Litmus milk: Alkaline. 



Potato : Moderate, grayish white, leathery 

 growth. 



Indole not produced. 



Nitrites produced from nitrates. 



Ammonia is produced. 



No acid from glucose, maltose, lactose, 

 sucrose, starch, glycerol or mannitol. 



Cellulose decomposed. Pllter paper strips 

 disintegrated at surface of liquid medium. 



Aerobic, facultative. 



Optimum temperature, 20° C. 



Source: Isolated from soil. 



Habitat: Soil. 



50. Pseudomonas nigrifaciens White, 

 1940. (Scientific Agriculture, 20, 1940, 643.) 



ni.gri.fa'ci.ens. L. niger black; L. v. 

 Jacio to make; M.L. part. adj. nigrofaciens 

 blackening. 



Rods, 0.5 by 1.5 to 2.0 microns, occurring 

 singly or in pairs and having rounded ends. 

 Actively motile with a single polar flagel- 

 lum. Gram-negative. 



Gelatin stab: Pigmented surface growth 

 after 24 hours. Slight crateriform liquefac- 

 tion changing to saccate. 



Agar colonies: Circular, convex, smooth, 

 glistening, entire, 2 to 4 mm in diameter. 

 Slight fluorescence in early stages. The me- 

 dium assumes a brownish color. 



Agar slant: Growth filiform, smooth, 

 moist, glistening, with blackish pigmenta- 

 tion at 4° and 15° C. in 48 hours, the medium 

 turning brownish. Slight fluorescence in 

 early stages. 



Broth: Turbid after 24 hours. After 5 to 6 

 days a black ring and then a pellicle forms, 

 later a black sediment. Medium turns 

 brown. 



Litmus milk: A black ring appears after 3 

 days at 15° C. followed by a pellicle. Litmus 

 is reduced. Alkaline reaction. No coagula- 

 tion. Digested with a putrid odor. 



Potato: No growth, even in presence of 

 1.5 per cent salt. 



Nitrites not produced from nitrates in 7 

 days. No gas produced. 



Starch is hydrolyzed. Natural fats not 

 hydrolj'zed. 



Alkaline reaction produced in sucrose, 

 maltose, lactose, glucose, mannitol and 

 raffinose broth (pH 8.2). No gas produced. 



Ammonia produced in peptone broth. 



Aerobic. 



Optimum pH, 6.8 to 8.4. 



Temperature relations: Minimum, 4° C. 

 Optimum, 25° C. Maximum, 33° to 35° C. 



