914 



MANUAL OF DETERMIXATIVE BACTERIOLOGY 



Filamentous organisms possessing a 

 tough shiny colony which is cartilagin- 

 ous, rarely producing an aerial mycelium, 

 though in certain strains, it may occur 

 frequently. Retains the mycelium form 

 for long periods. Not acid-fast. 



Gelatin: Liquefaction. 



In the young colony an orange -yellow 

 to orange-red intercellular pigment is 

 produced on all media, which may or 

 may not change to black as the culture 

 ages. 



Milk: No digestion. 



Starch is hydrolyzed. 



Does not utilize paraffin. 



Habitat : Soil. 



32. Nocardia rhodnii (Erikson) comb, 

 nov. {Actinomyces rhodnii Erikson, 

 Med. Res. Council Spec. Rept. Ser. 

 203, 1935, 37.) Named for the insect 

 genus, Rhodniiis. 



Description from Erikson {luc. cil., 

 p. 29). 



In early stages, the minute colonies are 

 composed of hyphal segments arranged in 

 angular apposition; the aerial mycelium 

 being short and straight. Later the 

 growth becomes extensive and spreading, 

 made up partly of long, genuinely branch- 

 ing filaments and partly of short segments 

 exhibiting slipping branching, each giving 

 rise to aerial hyphae. After 2 weeks the 

 angular branching is very marked, deli- 

 cate spreading herring-bone patterns 

 being formed. 



Gelatin : Rapid liquefaction ; pale pink 

 colonies in superficial pellicle and sedi- 

 ment. 



Coon's agar : Colorless pinpoint 

 colonies . 



Czapek's agar : Minute, colorless, round 

 colonies. 



Glucose agar: Abundant, coral pink, 

 convoluted, piled up growth. 



Glycerol agar: Extensive growth, dull 

 pink colonies round and umbilicated, be- 

 coming piled up and deeper coral ; later 

 partly submerged. 



Dorset's egg medium: Salmon-pink, 

 granular membrane; later piled up. 



Serum agar: Extensive, reddish, con- 

 fluent mass, granular, tending to be piled 

 up ; the medium around the growth shows 

 reddish coloration in 2 weeks. 



Inspissated serum: Smooth, round, 

 pale pink colonies, centrally depressed 

 and irregularly coiled larger mass ; no 

 liquefaction. 



Broth : Salmon-pink flakes in sediment 

 and colonies on surface; after 2 weeks 

 abundant growth, discoloration of me- 

 dium. 



Glucose broth : Thin, pink, superficial 

 pellicle, easil}' breaking up, and small 

 flakes in sediment ; after 2 weeks abun- 

 dant growth extending up tube. 



Synthetic sucrose solution: Colorless 

 to pink colonies in superficial pellicle, 

 and minute round white colonies co- 

 herent in loosely branching mass in 

 sediment. 



]Milk : Bright orange growth ; medium 

 unchanged. 



Potato agar: Abundant, pink growth, 

 piled up, scant stiff white aerial myce- 

 lium at top of slant. 



Source : From rcduvid bug, Rhodniiis 

 prolixus. 



33. Nocardia gardneri (Waksman) 

 comb. nov. (Actinomycete, Gardner and 

 Chain, Brit. Jour. Exp. Path., 23, 1942, 

 123; Proactinomijccs gardneri Waksman, 

 in Waksman, Horning, Welsch and Wood- 

 ruff, Soil Sci., 5J^, 1942, 289.) Named for 

 Prof. Gardner who first isolated this 

 organism. 



Gram-positive, branching mycelium. 



Gelatin : Cream-colored surface ring. 

 Rapid liquefaction. Green to greenish- 

 brown soluble pigment gradually diffuses 

 through the liquefied portion. 



Nutrient agar: Cream-colored, ele- 

 vated, lichenoid growth, soft, not 

 leathery; no aerial mycelium; very faint 

 brownish pigment. 



Glucose agar: Brownish, lichenoid 



