SPECIES OF NOCARDIA 133 



Mycelium: Straight, fine, 0.2 n thick; breaks up into small, coccoid 

 conidia. Acid-fast. 



Synthetic agar: Thin, spreading, orange growth. No aerial mycelium. 

 No soluble pigment. 



Nutrient agar: Much-folded, light yellow growth, becoming deep yellow 

 to yellowish red. No soluble pigment. 



Potato: Growth much wrinkled, whitish, becoming yellow to almost 

 brick-red. 



Gelatin: Yellowish surface growth. No growth in stab. No liquefaction. 



Milk: Orange-colored ring. No coagulation. No peptonization. 



Starch agar: Restricted, scant, orange growth. No hydrolysis. 



Glucose broth: Thin, yellowish pellicle. 



Nitrate: Reduction to nitrite. 



Temperature: Optimum 37°C. 



Source: Cerebral abscess in man. 



Pathogenicity: Transmissible to rabbits and guinea pigs but not to 

 mice. 



Remarks: A number of strains of acid-fast actinomycetes isolated from 

 human lesions have deviated in certain particulars from the description of 

 Nocardia asteroides, but not sufficiently to warrant separation as species. 



3. Nocardia polychromogenes (Vallee) Waksman and Henrici. (Vallee, 

 H., Ann. Inst. Pasteur, 17, 1903, 288; Jensen, H., Proc. Linnean Soc. N. S. 

 Wales, 56, 1931, 79, 363.) 



Mycelium: Long wavy filaments, 0.4-0.5 by 70-100 y., extensively 

 branched but without septa. Older cultures consist entirely of rods 4-10 n, 

 frequently in V, Y, or smaller forms. Still older cultures consist of shorter 

 rods and coccoid forms. Gram-positive, frequently showing bands and 

 granules. 



Nutrient agar: Scant, orange-red growth. 



Glucose agar: After 3 to 4 days raised, flat, glistening, rose-colored 

 growth; after 1 to 3 weeks becoming folded and coral-red. 



Gelatin : Growth along stab thin, yellowish, with thin radiating filaments. 

 Surface growth flat, wrinkled, red. No liquefaction. 



Milk: Growth starts as small orange-colored surface granules. After 1 

 to 2 weeks a thick, soft, orange-colored sediment forms. 



Glucose broth: After 3 to 4 days turbid; after 2 to 3 weeks an orange 

 flaky sediment. No surface growth. 



Temperature: Optimum 22°-25°C. 



Source: Blood of a horse; soil in France and Australia. 



Remarks: Differs from Nocardia corallina in the formation of very long 

 filaments and in filiform growth in gelatin stabs. 



