260 



THE ACTINOMYCETES, Vol. II 



Potato plug: Growth colorless, then 

 slightly yellowish or brownish. Aerial myce- 

 lium white to olive-colored. Color of plug 

 unchanged. Melanin-negative. 



Gelatin: 18-20°C. Growth colorless. No 

 aerial mycelium. Soluble pigment slightly 

 yellowish-brown. Gelatin liquefied. 



Milk: 37°C. Colorless to slight yellowish 

 growth. No aerial mycelium. Coagulation 

 with acid reaction, then peptonization. 



Starch: Hydrolysis weak to medium. 



Carbon utilization: Good growth with 

 arabinose, dextrin, fructose, galactose, glu- 

 cose, glycerol, maltose, mannitol, mannose, 

 raffinose, rhamnose, salicin, sorbose, starch, 

 sucrose, xylose, and sodium succinate. Scant 

 growth with esculin, inositol, lactose, sor- 

 bitol, sodium acetate, and citrate. 



Antagonistic properties: Produces anti- 

 tumor substances pluramycin A and B 

 (Maeda et al, 1956). 



Remarks: This culture is said to be re- 

 lated to S. vinaceus, but it does not produce 

 blue-red pigment in reverse of growth on 

 nutrient agar. 



192. Streptomyces poolensis (Taubenhaus, 

 1918) Waksman (Taubenhaus, J. J. J. Agr. 

 Research 13: 446, 1918). 



Morphology: Sporophores straight. Spores 

 oval to elliptical. 



Sucrose nitrate agar: Growth thin, color- 

 less. Aerial mycelium white to gray. 



Glucose-asparagine agar: Growth abun- 

 dant, glossy, light brown. 



Nutrient agar: Growth translucent, yel- 

 lowish to brown. Soluble pigment brown. 



Potato: Growth thin, reddish-brown. Sol- 

 uble pigment purplish. 



Gelatin: Liquefaction, with small, brown- 

 ish flakes in fluid. 



Milk: Brownish ring. Coagulation and 

 peptonization. 



Starch: Growth restricted, cream-colored. 

 No hydrolysis. 



Nitrate reduction: Positive. 



Antagonistic properties: Positive. 



Babitat: Sweet-potato disease known as 

 '•pox." 



19:;. Streptomyces praecox (Millard and 

 Burr, 1926) Waksman and Henrici, 1948 

 (Millard, W. A. and Purr, S. Ann. Appl. 

 Biol. 13: 580, 1926). 



.Morphology: Sporophores produce short, 

 open spirals. Spores spherical or oval, 0.8 

 n in diameter. 



Sucrose nitrate agar: Growth thin, color- 

 less. Aerial mycelium gray to olive-buff. ( )n 

 continued cultivation, aerial mycelium tends 

 to become white. 



Nutrient agar: Growth colorless. Aerial 

 mycelium white. 



Starch media: Growth thin, cream-col- 

 ored. Aerial mycelium white with greenish 

 tinge. Hydrolysis positive. 



Potato: Growth lichenoid, cream-colored 

 to light brown. Aerial mycelium white to 

 olive-buff. Soluble pigment olive-buff to 

 drab. On continued cultivation, no soluble 

 pigment produced. 



Gelatin: Growth good. Aerial mycelium 

 white. Liquefaction medium. Melanin-nega- 

 tive. 



Milk: Surface growth cream-colored, in 

 form of ring. Aerial mycelium white. Coagu- 

 lation slow; peptonization rapid. 



Nitrate: Reduction variable. 



Cellulose: Good growth, colorless. Aerial 

 mycelium dark gray. 



Tyrosinase reaction: Negative. 



Production of H 2 S: Negative. 



Temperature: Grows well at 37.5°C. 



( >dor: Very strong. 



Antagonistic properties: Represses growth 



of S. SCIlllil.S. 



Habitat: Knoblike scab of potatoes. 



Remarks: According to Ettlinger et al. 

 (1958), this organism belongs to the S. 

 griseus series. Hoffmann (1958) described a 

 culture of S. praecox that produced a light 

 to dark gray aerial mycelium and many 

 spirals; nonchromogenic. 



Type culture: IMRU 3374. 



