86 ACTINOMYCETES 



Remarks: Resembles Streptomyces griseocarneus. Utilizes xylose, fructose, 

 inositol, starch, dextrin, galactose, and maltose, but not arabinose, rham- 

 nose, dulcitol, and salicin. 



81. Streptomyces violaceoniger (Waksman and Curtis) Waksman 

 and Henrici. (Waksman, S. A., and Curtis, R. E., Soil Sci., 1, 1916, 111.) 



Synthetic agar: Colony at first dark gray, turning almost black, 2-4 

 mm in diameter. Surface glossy, much-folded, with very thin, gray margin. 

 Aerial mycelium white to gray after the colony is well developed. Pigment 

 bluish black at a later stage of growth. The pigment slowly dissolves in the 

 medium, turning almost black. Odor fairly strong. Microscopically two 

 types of mycelium are found: the thin, branching filaments of the substra- 

 tum, and the thick filaments of the aerial mycelium. The aerial mycelium 

 fragments not very rapidly, producing a few conidia, spherical and oval, 

 1.2-1.5 by 1.2-2.3 ju- These often occur in chains. 



Potato : Growth at first very slight, but after 48 hours develops into con- 

 tinuous, thick yellowish gray smear which later turns brown, with white 

 aerial mycelium covering the growth. Medium not colored. 



Gelatin: Growth gray; no aerial mycelium. Liquefaction rapid around 

 colony, but with no change in color. 



Synthetic solution: Colonies large, 2-3 mm in diameter, appearing at 

 the bottom and surface of the solution, but none throughout the medium. 

 Colonies bluish, with a regular margin. Medium not colored. 



Antagonistic properties: None; certain strains show activity. 



82. Streptomyces gedanensis (Lohlein) comb. nov. (Lohlein, M., Z. 

 Hyg., 63, 1909, 1-16.) 



Aerial mycelium: Hyphae short, gnarled; spores short, oval to spherical. 



Synthetic agar: Growth dark to almost black, with dark reverse. Aerial 

 mycelium abundant, mouse-gray. No soluble pigment. 



Nutrient agar: Growth thin, colorless. No aerial mycelium. No soluble 

 pigment. 



Glucose agar: Growth cream-colored, becoming black with light margin. 

 Aerial mycelium abundant, mouse-gray. 



Potato: Growth lichnoid, cream-colored to brownish. No aerial mycelium. 

 No soluble pigment. 



Gelatin: Growth thin, flaky. No soluble pigment. Liquefaction rapid. 



Milk: Surface ring cream-colored. No peptonization. 



Starch: Growth yellowish to cream-colored. Aerial mycelium light gray. 

 Hydrolysis strong. 



Nutrient broth : Growth on bottom of tube flaky. 



