2GG 



THE ACTINOMYCETES, Vol. II 



tive and gram-negative bacteria, as well as 

 against triehomonads and amoebae. 



206. Streptomyces resistomycificus Linden- 

 bein, 1952 (Lindenbien, W. Arch. Mikro- 

 biol. 17: 361-383, 19.52). 



Morphology: Sporophores long, with 

 curling tips. Spores short, oval. 



Glycerol nitrate agar: Growth yellow- 

 brown to dark brown. Aerial mycelium ash- 

 gray. Soluble pigment red-brown. 



Glucose-asparagine agar: Growth yellow- 

 brown. Aerial mycelium ash-gray. Soluble 

 pigment yellow-brown. 



Glycerol malate agar: Growth dark brown. 

 Aerial mycelium ash-gray to red-gray. 

 Soluble pigment gray to dark brown. 



Nutrient agar: Growth dark brown. 

 Aerial mycelium absent or lead-gray. Soluble 

 pigment dark brown. Melanin-positive. 



Glucose-peptone agar: Growth dark 

 brown. Aerial mycelium white. Soluble pig- 

 ment reddish to dark brown. 



Starch agar: Growth light yellow to red- 

 dish-brown. Aerial mycelium gray-white, 

 later red-gray. Soluble pigment lacking or 

 reddish-brown. Hydrolysis strong. 



Potato: Growth brownish-black. Aerial 

 mycelium reddish-white. Soluble pigment 

 dark brown. 



Gelatin: Growth dark brown. Aerial my- 

 celium white-gray. Soluble pigment chest- 

 nut-brown. Good liquefaction. 



Milk: Growth dark brown. Aerial myce- 

 lium white, later yellowish-red. Soluble pig- 

 ment dark brown. Peptonization none or 

 slight. 



Cellulose: No growth. 



Antagonistic properties: Produces resisto- 

 niycin, which is active against gram-positive 

 bacteria. 



Remarks: Gause et al. (1 ( .)57) have de- 

 scribed certain closely related forms, such as 

 .1. griseorubiginosus with a variety .spiralis, 

 .•iihI .1. variabilis with a variety roseolas. 



Type culture: IMRU 3058. 



207. Streptomyces reticiili (Waksman and 

 Curtis, 19 Hi; Waksman, 1919) Waksman and 

 Henrici, 1 ( .)48 (Waksman, S. A. and Curtis, 

 R. E. Soil Sci. 1: 118, 1916; Waksman, S. A. 

 Soil Sci. 8: 143, 1919). 



Morphology: Aerial mycelium gives rise 

 to simple verticils. Sporophores straight or 

 spiral-shaped (sinistrorse) on different media. 

 Spores spherical or oval, smooth, 1.0 to 1.4 

 H in diameter (PI. I a). 



Sucrose nitrate agar: Growth colorless, 

 with yellowish tinge, becoming brownish. 

 Aerial mycelium thin, cottony, white to ash- 

 gray. No soluble pigment. 



Glycerol malate agar: Growth colorless. 

 Aerial mycelium yellowish. No soluble pig- 

 ment. 



Nutrient agar: Growth wrinkled, gray, 

 becoming brownish. No aerial mycelium. 

 Soluble pigment dark brown. 



Potato: Growth gray, with black center. 

 Aerial mycelium ash-gray. Soluble pigment 

 black. 



Gelatin: Growth gray to brown. Aerial 

 mycelium white. Soluble pigment faint 

 brown to dark brown. Good liquefaction. 



Milk: Coagulation rapid; peptonization 

 slow. 



Starch: Growth brownish-gray. Hydrol- 

 ysis. 



Cellulose: Scant growth. 



Nitrate reduction: Positive. 



Production of H 2 S: Positive. 



Invertase: Positive. 



Temperature: Optimum 25°C. 



Antagonistic properties: Some strains 

 product 1 neomycin or a neomycin-like sub- 

 stance. Some strains reduce double bonds in 

 certain steroids. 



Habitat: Soil. 



Remarks: According to Ettlinger et al. 

 (1958), the verticils are both primary and 

 secondary; no spirals were observed. They 

 also report the species to be melanin-nega- 

 tive. One wonders whether they had a typi- 

 cal culture. This culture was later found to 



