64 ACTINOMYCETES 



tinge. Aerial mycelium abundant. Soluble pigment light brown. Superficial 

 droplets amber-colored. 



Nutrient agar: Growth luxuriant; aerial mycelium moderate, white. Sol- 

 uble pigment deep brown. 



Glucose agar: Aerial mycelium gray. Soluble pigment deep brown. 



Potato: Growth wrinkled and raised, pale ocherous buff; soluble pigment 

 brown to black. 



Gelatin: Liquefaction slight. 



Milk: Surface growth patchy, white; aerial mycelium gray. Hydrolysis 

 gradual. 



Starch: Growth abundant; aerial mycelium white, becoming gray. Hy- 

 drolysis slight. 



Nutrient broth: Surface pellicle, abundant, white; soluble pigment deep 

 brown. 



Glucose-asparagine agar: Growth luxuriant; aerial mycelium white to 

 mouse-gray. Soluble pigment light amber. 



Antagonistic properties: Strongly antagonistic. Produces streptomycin. 



Source : Soil from Bikini atoll. 



45a. Strep tomyces mirabilis Ruschmann (Ruschmann, G. Die Phar- 

 mazie, 7, 1952, 542-550, 639-648, 823-831.) 



Aerial mycelium: White, fluffy layer, consisting of abundant aerial my- 

 celium and spores. Hyphae straight, without spirals or curvature; sporula- 

 tion takes place after 6-7 days. 



Nutrient agar: Poor growth; slimy surface, resembling that of bacteria. 

 No sporulation. 



Glucose agar: Grayish brown, shiny growth. No aerial mycelium even 

 after 14 days. Soluble brown pigment. 



Potato: Good, lichnoid growth; dark brown to black, soluble pigment. 



Gelatin: Good flaky growth. Rapid liquefaction. Dark brown to black 

 soluble pigment. 



Milk: Surface growth with white, fluffy aerial mycelium. Coagulation and 

 peptonization. Liquefied portion colored black. Reaction of medium un- 

 changed. 



Czapek's solution: Limited growth in the form of a few surface colonies, 

 sinking rapidly to bottom. 



Carrot juice agar: Good growth in form of round colonies, covered with 

 white aerial mycelium. Each colony produces 3 to 5 cracks or holes in center. 



Temperature: Optimum at 29°C. No growth at 37°C. 



Oxygen requirement: Quite considerable. 



Fats: Readily utilized. 



Antagonistic properties: Produces miramycin. Antagonistic effect strong- 



