SPECIES OF STREPTOMYCES 49 



21. Streptomyces aureofaciens Duggar. (Duggar, B. M., Ann. N. Y. 



Acad. Sci., 51, 1948, 177.) 



Vegetative growth: Mycelium hyaline, becoming yellow in 2-3 days; 

 later golden tan to tawny. 



Aerial mycelium: White, becoming brownish gray to dark, drab-gray in 

 5-7 days. 



Nutrient agar: Growth characteristic, with golden yellow soluble pig- 

 ment. 



Potato: Soluble pigment golden yellow. 



Antagonistic properties : Produces chlortetracy cline, an amphoteric com- 

 pound containing both nitrogen and nonionic chlorine, active against vari- 

 ous bacteria, rickettsiae, and the larger viruses. 



22. Streptomyces albidoflavus (Rossi Doria) Waksman and Henrici. 

 (Rossi-Doria, T., Ann. 1st. Ig. Sper. Roma N. S. 1, 1894, 399^38.) 



Synthetic asparagine agar: Growth rapidly covered with white aerial 

 mycelium, later becoming whitish yellow; brown on reverse side; yel- 

 lowish soluble pigment. 



Peptone agar: Growth cream-colored, covered with fine white aerial 

 mycelium; yellow soluble pigment. 



Tyrosine agar: Growth fine with orange-yellow on reverse side; medium 

 becomes yellowish to yellowish rose. 



Synthetic asparagine solution: Long branching filaments, 0.6 y. in diam- 

 eter. Thicker aerial mycelium producing irregular spores; flaky growth 

 dropping to bottom of tube. Surface growth becomes covered with yellow- 

 ish white aerial mycelium; brownish on reverse side; soluble pigment 

 yellowish. 



Peptone solution: Growth rapid, much folded, partly covered with white 

 mycelium on surface of medium; soluble yellow-ocher pigment. 



Gelatin: Punctiform colonies with white aerial mycelium on surface of 

 liquid; no soluble pigment; liquefaction rapid. 



Milk: Growth rapid, becoming covered with whitish aerial mycelium; 

 never fully covering the surface; no coagulation; peptonization begins 

 slowly and is completed in 13 days, liquid becoming yellowish orange. 



Starch : Growth cream-colored, rapidly covered with yellow aerial myce- 

 lium; after 20 days, growth becomes much folded; greenish on reverse 

 side; slight amber color in medium. 



Coagulated serum: Cream-colored growth of surface becoming covered 

 with white aerial mycelium; liquefaction rapid. 



Antagonistic properties: Positive. 



Remarks: This strain is closely related to Streptomyces albus. 



