FAMILY STREPTOMYCETACEAE 



957 



Nocardia thermophila Chalmers and 

 Christopherson, Ann. Trop. Med. and 

 Parasit., 10, 1916, 271.) From Greek 

 thermus, heat and phihis, loving. 



Description from Waksman, Umbreit 

 and Gordon, Soil Sci., 47, 1939, 49. 



Hyphae straight, conidia formed. 



Gelatin: Liquefaction. 



Czapek's agar : At 28°C, deep colorless 

 growth, thin white aerial mycelium; no 

 soluble pigment. 



Starch agar : Yellowish growth with 

 white-gray, powdery aerial mycelium. 



Milk: Proteolysis. 



Potato plug : Yellowish growth with no 

 aerial mycelium, the plug usually being 

 colored brown. 



Starch is hydrolyzed. 



No pigment produced on nutrient agar 

 or gelatin. 



Temperature relations : Optimum 50°C. 

 Good growth at 28°C. Usually no 

 growth at 60°C. Some strains are in- 

 capable of growing at 28°C, whereas others 

 seem to grow well even at 65°C. 



Aerobic. 



Habitat: Soil, hay, composts. 



58. Streptomyces thermofuscus (Waks- 

 man, Umbreit and Gordon) comb. nor. 

 (Actinomyces thermofuscus Waksman, 

 Umbreit and Gordon, Soil Sci., 47, 

 1939, 49.) From Greek thermus, heat 

 and Latin fuscus, dark. Presumably 

 derived to mean heat -loving and dark in 

 color. 



Hyphae spiral -shaped; conidia pro- 

 duced. 



Gelatin: Liquefaction. At 50°C, a 

 grayish ring is produced and soluble pig- 

 ment is formed. At 28°C, growth with 

 no soluble pigment. 



Czapek's agar : Poor growth at 28°C, 

 deep-gray, with but little aerial myce- 

 lium. At 50°C, growth dark to violet, 

 with gray to lavender aerial mycelium 

 and soluble brown pigment. 



Milk: Proteolysis. 



Potato : Abundant , dark-colored 

 growth, no aerial mycelium, or few white 

 patches, dark soluble pigment. 



Starch is hydrolyzed. 



Temperature relations : Good growth 

 at 50° and 60°C. Will grow at 65°C. 

 Faint growth at 28°C. 



Aerobic . 



Distinctive characters : This species is 

 distinguished from Streptomyces thermo- 

 philus by the brown-colored aerial myce- 

 lium on synthetic media, spiral-shaped 

 hyphae, and ability to grow readily at 

 65°C. 



Habitat: Soils and composts. 



59. Streptomyces scabies (Thaxter) 

 comb. nov. (Oospora scabies Thaxter, 

 Ann. Rept. Conn. Agr. Exp. Sta., 1891, 

 153; Actinomyces scabies Gussow, 

 Science, N. S. 39, 1914, 431.) From 

 Latin scabies, scab. 



Wavy or slightly curved mycelium, 

 with long branched aerial hyphae, show- 

 ing a few spirals. Conidia more or less 

 cylindrical, 0.8 to 1.0 by 1.2 to 1.5 mi- 

 crons . 



Gelatin stab : Cream-colored surface 

 growth, becoming brown. Slow lique- 

 faction. 



Synthetic agar: Abundant, cream- 

 colored, wrinkled, raised growth. Aerial 

 mycelium white, scarce. 



Starch agar : Thin, transparent, spread- 

 ing growth. 



Glucose agar: Restricted, folded, 

 cream-colored, entire growth. 



Plain agar: Circular, entire colonies, 

 smooth, becoming raised, lichenoid, 

 wrinkled, white to straw-colored, opales- 

 cent to opaque. 



Glucose broth: Ring in form of small 

 colonies, settling to the bottom. 



Litmus milk : Brown ring with greenish 

 tinge ; coagulated ; peptonized with alka- 

 line reaction. 



Potato : Gray, opalescent growth, be- 

 coming black, wrinkled. 



Nitrites produced from nitrates. 



Brown soluble pigment formed. 



Starch is hydrolyzed. 



Optimum temperature 37°C. 



Aerobic . 



The potato scab organism, like other 



