■82 



ORDER V. ACTINOMYCETALES 



yellowish tinge, becoming brownish, spread- 

 ing. Aerial mycelium thin, white, cottony. 



Starch agar: Brownish gray growth. 



Glucose agar: Restricted, brownish 

 growth; center raised. 



Glucose broth: Sediment consisting of 

 large colonies. 



Litmus milk: Reaction unchanged; co- 

 agulated; peptonized. 



Potato: Gray growth with black center. 



Starch is hydrolyzed. 



Dark brown pigment formed. 



Nitrites produced from nitrates. 



Aerobic. 



Optimum temperature, 25° C. 



Antagonistic properties: Some strains 

 produce neomycin or a neomycin-like sub- 

 stance. 



Source: Isolated from upland and adobe 

 soils in California. 



Habitat: Soil. 



64. Streptomyces netropsis Finlay and 

 Sobin, 1952. (U. S. Pat. 2,586,762, Feb. 19, 

 1952.) 



ne.trop'sis. Gr. neut.n. netruni spindle; 

 Gr. fem.n. opsis appearance of something; 

 M.L. adj. netropsis spindle-like. 



Vegetative growth : Slightly elevated with 

 rough surface and smooth edge and with 

 brown reverse. 



Aerial mycelium: White. Sporophores on 

 tips of short hyphae in form of whorls or 

 terminal clusters of short hyphae. Conidia 

 short, cylindrical, 0.7 by 1.3 microns. 



Gelatin: Moderate surface growth. White 

 aerial mycelium. Soluble dark brown pig- 

 ment. No liquefaction. 



Agar: Moderate to good light brown 

 growth. White aerial mycelium. Soluble 

 light brown pigment. 



Synthetic agar: Thin, pale olive-buff 

 growth. Aerial mycelium pale vinaceous 

 fawn. No soluble pigment. 



Glucose asparagine agar: Moderate, 

 wrinkled growth. White aerial mycelium. 

 Soluble brown pigment. 



Ca-malate agar: Moderate, cream to 

 buff growth. White aerial mycelium. No 

 soluble pigment. 



Starch agar: Moderate thin growth with 

 pale olive-buff reverse. White aerial myce- 

 lium. No soluble pigment. 



Glucose agar: Good, dark brown growth. 

 White aerial mycelium. Soluble brown pig- 

 ment. 



Milk: Poor growth. Not peptonized. 



Potato: Poor, waxy, wrinkled, brown 

 growth. No aerial mycelium. Dark brown 

 pigment. 



Starch is actively hydrolyzed. 



Nitrites not produced from nitrates. 



Antagonistic properties : Produces a basic 

 antibiotic, netropsin. 



Source: Isolated from soil near Hudson, 

 New York. Cultural characteristics de- 

 scribed are those of isolate No. 2937-6. A 

 culture has been deposited with the Fer- 

 mentation Division of the Northern 

 Regional Research Laboratory, Peoria, Illi- 

 nois, permanent collection number NRRL- 

 2268. 



Habitat: Soil. 



65. Streptomyces verticillatus (Kriss, 

 1938) Waksman, 1953. {Actinomyces verti- 

 cillatus Kriss, Microbiologia, 7, 1938, 111; 

 Waksman, in Waksman and Lechevalier, 

 Actinomycetes and Their Antibiotics, Balti- 

 more, 1953, 75.) 



ver.ti.cil.la'tus. L. mas.n. verticillus a 

 whorl; M.L. adj. verticillatus whorled. 



Vegetative growth: Colorless or slightly 

 brownish, smooth or rough colonies. 



Aerial mycelium: Characteristic primary 

 whorl; formation of straight sporophores. 

 Spores cylindrical, oblong, 0.8 by 1.0 to 1.9 

 microns. 



Gelatin: Rapid liquefaction. 



Agar: Brown growth with no aerial my- 

 celium. Soluble brown pigment. 



Synthetic agar: Well developed, velvety 

 aerial mycelium, at first white, later dark 

 gray or gray-green. 



Milk: Coagulated and peptonized. 



Potato: Soluble brown pigment. 



Sucrose is inverted. 



Starch is hydrolyzed. 



No growth on cellulose. 



Nitrites rapidly produced from nitrates. 



Antagonistic properties: Weak. 



Relationships to other species: Strepto- 

 myces verticillatus viridans is described as a 

 substrain. 



Source: Isolated from rhizosphere of 

 wheat, Transvolga region, U.S.S.R. 



