172 



THE ACTINOMYCETES, Vol. II 



Potato: Growth white, becoming brown- 

 ish to rust-colored. Plug colored black. 



Tyrosine agar: Growth white with a 

 brownish reverse. Soluble pigment brownish. 



Milk: Coagulation and peptonization. 



Coagulated serum: Growth cream-colored. 

 No aerial mycelium. No soluble pigment. 

 Rapid liquefaction of serum. 



Remarks: This organism is considered as 

 a transitional form between S. albas and S. 

 viridis. Krassilnikov (1949) considered it as 

 a variety of A. viridochromogenes. 



15. Streptomyces albus (Rossi-Doria, 1891; 

 emend. Gasperini, 1892) Waksman and Hen- 

 rici, 1948 (Rossi-Doria, T. Ann. ist. ig. sper. 

 Roma, n. s. 1: 399-438, 1894). 



Synonym: Numerous synonyms of this 

 species are found in the literature. They 

 belong mostly to the species-group "S. albus.'" 

 Many of them are listed in Chapter 6, under 

 the corresponding group. 



Morphology: Sporophores produce long 

 spirals. Spores spherical to oval. Some strains 

 produce, according to Okami, straight sporo- 

 phores, depending on the composition of the 

 medium. 



Agar media: Growth colorless; may be- 

 come yellowish to brown with age. No 

 soluble pigment formed, although some 

 strains may excrete a brownish substance in 

 certain media and under certain conditions. 

 Aerial mycelium abundant, white; the shade 

 of color varies with composition of medium 

 from snow-white to somewhat yellowish. 



Sucrose nitrate agar: Substrate growth 

 smooth, colorless. Aerial mycelium cottony 

 to powdery; white to snow-white. 



Glucose-asparagine agar: Aerial mycelium 

 gray, becoming brownish. 



Nutrient agar: Generally no aerial my- 

 celium; chalky white deposit on old colonies. 



Potato: Growth lichenoid, cream-colored. 

 Aerial mycelium white. 



Gelatin: Colonies gray. No soluble pig- 

 ment. Strong liquefaction. 



Milk: Surface ring cream-colored. Aerial 

 mycelium white. Peptonization rapid. 



Starch agar: Aerial mycelium white. 

 Rapid hydrolysis of starch in some cultures; 

 others show little or no hydrolysis. 



Nitrate: Reduction to nitrite positive. 



Production of H 2 S: Negative. 



Odor: Characteristic, moldy. 



Antagonistic properties: Certain strains 

 are active upon gram-positive bacteria. Some 

 produce actinomycetin, others form thiolut in 

 or endomycin. 



Habitat: Occurs in dust and soil. 



Remarks: The general occurrence of this 

 species, the ease of its superficial identifica- 

 tion, and the fact that it has been adopted 

 as the type species for the genus Strepto- 

 myces, justify a more complete characteri- 

 zation, as given in Chapter 6. Numerous 

 strains of this species, varying in their 

 cultural and other properties have been 

 reported. Numerous descriptions of closely 

 related organisms also are found in the 

 literature (Duche). Krassilnikov lists 18 

 strains and substrains (A. albus vulgaris, A. 

 albus chlamydosporus, etc.). .4. longisporus 

 Krassilnikov (1949) and some of the sub- 

 strains, like A. longisporus griseus, belong to 

 this group. Solovieva and Rudaya (Anti- 

 biotiki, 4(6): 5-10, 1959) list a variety fun- 

 gatus capable of producing an antifungal 

 agent, albofungin. 



Type culture: IMRU 3005. 



16. Streptomyces althioticus Yamaguchi 

 et al., 1957 (Yamaguchi, H., Nakayama, 

 Y., Takeda, K., Tawara, K., Maeda, K., 

 Takeuchi, T., and Umezawa, H. J. Anti- 

 biotics (Japan) 10A: 195-200, 1957). 



Morphology: Curved chains or spirals of 

 oval spores on ends of aerial sporophores. 

 Frequently, tips of aerial mycelium divided 

 into tufts of spore chains. 



Sucrose nitrate agar: Growth colorless i<> 

 white, later light brown to purplish. Aerial 

 mycelium powdery white, later gray. 



