98 ACTINOMYCETES 



Gelatin: Growth yellow, changing to red, with hyaline margin. Liquefac- 

 tion slow. 



Milk: Ring scant, pink. No coagulation. No peptonization. 



Starch: Growth thin, spreading, transparent, with red tinge. Hydrolysis 

 ready. 



Glucose broth: Surface ring pinkish. 



Nitrate: Reduction to nitrite. 



Temperature: Optimum 37°C. 



Antagonistic properties: Positive. 



104. Streptomyces purpurascens Lindenbein. (Lindenbein, W., Arch. 

 Mikrobiol., 17, 1952, 361-383.) 



Vegetative growth: Usually heavy, red to carmine-red to almost purple. 



Aerial mycelium: Cottony, white. Spirals observed in 6 days, but they 

 may be lacking altogether. 



Synthetic agar: Growth typical carmine-red. Aerial mycelium cottony, 

 chalk-white. Soluble pigment brown-red. 



Nutrient agar: Growth light brown, with dark brown reverse. Aerial 

 mycelium velvety, gray. 



Glucose agar: Growth lichnoid, red to red-brown. Aerial mycelium cot- 

 tony, chalk- white. Soluble pigment light brown. 



Potato: Growth very good, brownish to reddish. Aerial mycelium velvety, 

 white. No soluble pigment. 



Gelatin: Surface growth heavy, light-brown. Aerial mycelium cottony, 

 white. Soluble pigment red-brown. Liquefaction rapid. 



Milk: Growth lichnoid, red to dark brown. Aerial mycelium velvety to 

 cottony, white. No proteolysis. 



Starch: Growth lichnoid, light-carmine-colored. Aerial mycelium white. 

 No soluble pigment. Hydrolysis strong. 



Cellulose: Growth very good, white to red. 



Glucose broth: Pellicle heavy, with limited bottom growth, carmine-red 

 later copper-red. Aerial mycelium powdery, chalk- white. Soluble pigment 

 carmine-red. 



Glucose-asparagine agar: Growth carmine-red. Aerial mycelium cottony, 

 white. Soluble pigment orange. 



Calcium malate agar: Growth carmine-red. Aerial mycelium chalk-white. 

 Soluble pigment brick-red. 



Antagonistic properties: Produces rhodomycin. 



Remarks: On continued growth on synthetic media the culture may lose 

 the property to produce the typical pigment. It can be regained, however, 

 by growth on organic media. 



