44 ACTINOMYCETES 



Growth: Filaments with close branching of the hyphae. Capacity to 

 produce aerial mycelium lost on cultivation. 



Synthetic agar: Growth abundant, spreading, lichnoid, glossy, yellowish 

 becoming brownish. 



Nutrient agar: Colonies small, grayish, with depressed center, becoming 

 wrinkled. 



Glucose agar: Growth abundant, lichnoid, center raised, gray with pur- 

 plish tinge, entire. 



Potato: Growth cream-colored, becoming gray, wrinkled. 



Gelatin: Colonies small, cream-colored. Liquefaction rapid. 



Milk: Ring pinkish brown. Coagulation and rapid peptonization. 



Starch: Growth scant, restricted brownish; hydrolysis rapid. 



Cellulose: Growth good. 



Glucose broth: Sediment flaky. 



Nitrate: Nitrites produced. 



Temperature: Optimum 37 °C. 



Antagonistic properties: Limited activity against some bacteria. 



Remarks: Soluble green pigment produced when freshly isolated. In 

 time, this pigment becomes brown. 



12. Streptomyces viridans (Krassilnikov) comb. nov. (Krassilnikov, 

 N. A., Actinomycetales, Akad. Nauk. USSR, Moskau, 1941, 33.) 



Vegetative growth: Colonies green to brown-green. 

 Aerial mycelium: Dark gray, olive-colored, or gray-green velvety, cover- 

 ing the whole colony. Sporophores long, spiral-shaped. Spores cylindrical. 

 Synthetic agar: Colonies green; soluble green pigment produced. 

 Nutrient agar: Growth brown-green; soluble brown substance produced. 

 Gelatin: Liquefaction rapid. 

 Milk: Coagulation and rapid peptonization. 

 Starch: Hydrolysis rapid. 

 Cellulose: Growth poor. 

 Nitrate: Reduction strong. 

 Sucrose: Inversion rapid. 

 Antagonistic properties: None; some strains are weakly active. 



13. Streptomyces californicus (Waksman and Curtis) Waksman 

 and Henrici. (Waksman, S. A, and Curtis, R. E., Soil Sci., *, 1916, 122). 



Aerial mycelium: Filaments with long, narrow, open spirals. Spores 

 spherical to oval. 



Synthetic agar: Growth spreading, vinaceous-colored. Aerial mycelium 

 powdery, thin, light neutral gray. No soluble pigment. 



Nutrient agar: Growth thin, restricted, yellowish to cream-colored. 



