Waksman — 42 — Actinomycetes 



and other bacteriological dyes. The spores are uninucleate, as deter- 

 mined by Giemsa staining. 



The two strains of S. venezuelae were similar, in their cultural 

 and physiological properties, to S. lavendulae, although they differed 

 from S. lavendulae in their ability to utilize various carbohydrates. 

 The former utilized arabinose, rhamnose, xylose, lactose and fructose. 

 The utilization of these by S. lavendulae was either negative or ques- 

 tionable. The two sti-ains also differed from S. lavendidae in their 

 sensitivity to actinophage and in serological reactions. 



Strcptomyces antihioticus (Waksman and Woodruff) 

 Waksman and Henrici 



A detailed description of S. antihioticus has been given by Waks- 

 man and Woodruff (491). 



Morphology: Spore-bearing hyphae produced in the form of straight aerial 

 mycelium. The sporophores are arranged in clusters; no spirals formed. The 

 spores are nearly spherical to somewhat elliptical. 



Gelatin: Dark brown growth on surface, with patches of gray aerial mycelium. 

 Dark pigment produced, which gradually diffuses into the unliquefied part of 

 gelatin. Liquefaction of gelatin at first very slow, later becoming rapid. 



Potato plug: Folded, brown-colored growth, with a thin black ring on plug, 

 fading into a bluish tinge. No aerial mycelium. 



Carrot plug: Cream-colored to faint brownish growth. No aerial mycelium. 

 No pigment. 



Litmus milk: Thick, brownish ring on surface of milk. Mouse-gray aerial 

 mycelium with greenish tinge; growth becomes brown, especially in drier portions 

 adhering to glass. No reaction change, no coagulation of milk, no clearing; 

 whitish sediment at bottom of tube. Old cultures— heavy growth ring on surface 

 of milk, heavy precipitation on bottom; liquid brownish to black in upper portion. 



Czapek's agar: Thin, whitish growth. Thin, gray aerial mycelium. 



Peptone media: Production of dark pigment at early stage of growth is very 

 characteristic. Growth brownish, thin, with yellowish-gray to yellowish-green 

 aerial mycelium. 



Odor production: Very characteristic soil odor. 



Antagonistic properties: Has a marked antagonistic effect on gram-positive 

 and gram-negative bacteria (much more so on the former than on the latter), as 

 well as on actinomycetes. It is also active against fungi, which vary in degree 

 of sensitivity. 



Habitat: Found in soil. Isolated on Escherichia coli washed agar plate, using 

 living cells of E. coli as the only source of available nutrients. 



Stre'ptomyces aureofaciens Duggar 



S. aureofaciens, the organism that produces aureomycin, was isolated 

 from the soil (99fl). 



