214 



THE A.CTINOMYCETES, Vol. II 



numerous spirals on most synthetic media. 

 Spores spherical to oval. 



Glycerol nitrate agar: Growth colorless. 

 Aerial mycelium white to grayish. 



Glucose-asparagine agar: Growth color- 

 less. Aerial mycelium white to grayish. Solu- 

 ble pigment sometimes yellowish. 



Calcium malate agar: Growth colorless to 

 yellowish. Aerial mycelium white to grayish. 

 Soluble pigment of some strains pink; later 

 disappears. 



Nutrient agar: Soluble pigment absent or 

 slightly yellowish-brown. Melanin-negative. 



Starch agar: Growth colorless to yellowish. 

 Aerial mycelium white to grayish. Strong 

 hydrolysis. 



Potato: Growth yellowish to grayish. 

 Aerial mycelium absent or white to grayish. 

 A deep brown soluble pigment around the 

 growth may be produced. 



Milk: Growth colorless to cream-colored. 

 Soluble pigment absent or slightly brown. 

 Coagulation and peptonization weak. 



Gelatin: Growth colorless to cream- 

 colored. Soluble pigment absent or faint 

 brown. Positive liquefaction. 



Nitrate: No, or doubtful reduction. 



Tyrosinase: Some strains positive. 



Antagonistic properties: Produces a poly- 

 ene-type antifungal substance, fungicidin. 



Remarks: Two groups of this species were 

 recognized; Group A produces nonspiral- 

 forming sporophores; aerial mycelium white; 

 violet pigment on potato. It is thus differ- 

 entiated from Group G, described above. 



93. Streptomyces fuscus (Sohngen and Fol, 

 llilli Waksman (Sohngen, N. L. and Fol, 

 J. G. Centr. Bakteriol. Parasitenk. Abt. II, 

 40: 89-98, 1914). 



Morphology: According to Krassilnikov, 

 the organism forms short straight sporo- 

 phores arranged in fascicles or clusters in the 

 form of brushes. 



Agar media: Growth irregular, dry, color- 

 less to stone-red. Aerial mycelium initially 

 white, later becoming dark brown. Spores 



rose-colored. Some strains excrete a brown 

 substance in protein media. 



Carbohydrates: Slight decomposition; 

 even glucose is assimilated with difficulty. 



Carbon utilization: Best sources are 

 calcium salts of various organic acids, rang- 

 ing from malic and citric to stearate and 

 palmitate. Formate not utilized. 



Nitrogen utilization: Ammonium chloride 

 and asparagine, nitrate, and peptone assimi- 

 lated with difficulty. 



Paraffins: Assimilated. 



Rubber: Brown-red growth. Rubber de- 

 composed. 



Temperature: Optimum 33°C; maximum 

 37°C. Destroyed in 5 minutes at 65°C. 



Habitat: Soil. 



94. Streptomyces galbus Frommer, 1959 

 (Frommer, W. Arch. Mikrobiol. 32: 195, 



1959). 



Morphology: Sporophores monopodially 

 branched, ending in spirals with 3 to 8 turns. 

 On some media, certain strains produce long, 

 straight, slightly branched aerial hyphae, 

 with short side branches. 



Glycerol nitrate agar: Growth abundant; 

 reverse yellow to yellow-green. Aerial 

 mycelium cream-colored, mouse-gray, or 

 green-gray. Soluble pigment golden yellow, 

 later turning green-yellow. 



Glucose-asparagine agar: Growth weak, 

 crusty, reverse light yellow or green-yellow, 

 later turning brown. Aerial mycelium thin, 

 powdery, mouse-gray with white spots. 

 Soluble pigment yellowish to yellow-green. 



Calcium malate agar: Growth yellow to 

 greenish-yellow. Aerial mycelium white to 

 brownish-gray. Soluble pigment yellow to 

 yellow-green. 



Nutrient agar: Growth thin, brown. Xo 

 aerial mycelium. Soluble pignieni brown. 



Starch-KN< > : , agar: Growth yellow. Aerial 

 mycelium white to white-gray. Soluble pig- 

 nieni yellow. Slow hydrolysis of starch. 



Potato: Growth heavy, yellow to reddish- 

 brown. Aerial mycelium powdery, white. 



