SPECIES OF NOCARDIA 159 



41. Nocardia gardneri (Waksman) Waksman and Henrici. (Gardner, 

 A. D., and Chain, E., Brit. J. Exptl. Pathol., 23, 1942, 123; Waksman, 

 in Waksman, S. A., Horning, E. S., Welsch, M., and Woodruff, H. B., Soil 

 Sci., 54, 1942, 289.) 



Mycelium: Gram-positive, branching. 



Nutrient agar: Cream-colored, elevated, lichnoid growth, soft, not 

 leathery; no aerial mycelium; very faint brownish pigment. 



Glucose agar: Brownish, lichnoid growth, with wide, cream-colored edge; 

 white to grayish aerial mycelium gradually covering surface. Reverse of 

 growth yellowish; no soluble pigment. 



Potato: Barnacle-like, brownish, spreading growth; no aerial mycelium. 

 Medium brownish around growth. 



Gelatin: Cream-colored surface ring. Rapid liquef action. Green to green- 

 ish brown soluble pigment gradually diffuses through the liquefied portion. 



Glucose-asparagine agar: Aerial mycelium develops slowly. 



Tryptone broth: Growth occurs as small pellets at the base of the flask; 

 later, a thin surface pellicle appears, which consists of a branching my- 

 celium. Black pigment slowly produced. 



Temperature: Good growth at 25°; slow growth at 37°C. 



Source: Isolated as an air contaminant at Oxford, England. 



Remarks: On synthetic and organic media, produces an antibiotic sub- 

 stance (proactinomycin) which is primarily active against various gram- 

 positive bacteria. Indole not formed. No acid from glucose, lactose, mal- 

 tose, mannitol, sucrose, and dulcitol. 



42. Nocardia fordii (Erikson) comb. nov. (Erikson, D., Med. Research 

 Council Spec. Rept. Ser. 203, 1935.) 



Mycelium: Filaments of medium length, no spirals or markedly wavy 

 branches. Short, straight, sparse aerial mycelium. Small oval conidia on 

 potato agar and starch agar. 



Nutrient agar: Small, creamy golden, ring-shaped colonies, and heaped- 

 up patches, becoming golden brown and convoluted. 



Potato: Yellowish growth in thin line, terminal portion tending to be 

 piled up, scant, white aerial mycelium at top of slant; after 12 days, 

 growth abundant, golden brown, confluent, partly honeycombed, partly 

 piled up. 



Gelatin: No visible growth, slight softening in 20 days; half-liquefied 

 after 40 days. 



Milk: Coagulated, brownish surface ring. 



Starch: No hydrolysis. 



Nutrient broth: Few flakes at first; later abundant coherent puffball 

 growth. 



