Description of 



Species of Micromonospora 



1. Micromonospora chalcea (Foulerton) Orskov. (Foulerton, A., 

 Lancet, 1, 1905, 1200; Orskov, J., Investigations into the morphology of 

 the ray fungi, Copenhagen, 1923.) 



Vegetative growth: Rapid growth on all nutrient media, especially on 

 glucose-asparagine agar. Growth heavy, compact, raised, pale pink to 

 deep orange, not spreading much into the medium. Hyphae long, thin, 

 branching, nonseptate. Surface of growth smooth or folded, dull or shining. 

 No soluble pigment. 



Aerial mycelium: None. Spore-layer well developed, moist and glisten- 

 ing, brownish black to greenish black; color sometimes spreading through 

 the whole mass of growth. Conidia oval or spherical, formed individually 

 on relatively nonbranching conidiophores. 



Gelatin: Liquefaction positive. 



Milk: Peptonization, occasional coagulation. 



Starch: Hydrolysis positive. 



Cellulose: Rapid decomposition. 



Nitrate: Reduction to nitrite. 



Sucrose: Inversion positive. 



Proteolytic action seems stronger in this than in the other species of 

 this genus. 



Temperature: Optimum for growth 30°-35°C. Thermal death point of 

 mycelium, 70°C in 2 to 5 minutes. Spores resist 80°C for 1 to 5 minutes. 



Source: Soil, lake mud, and other substrates. 



2. Micromonospora fusca Jensen. (Jensen, H., Proc. Linnean Soc. 



N. S. Wales, 57, 1932, 178.) 



Vegetative growth : On glucose-asparagine agar heavy, compact, orange- 

 colored, rapidly changing to deep brown and nearly black. Deep brown 

 soluble pigment. 



Aerial growth: Spore-layer moist, glistening, grayish to brownish black. 



Gelatin: Liquefaction weak. Grows in liquid media as small brown 

 granules and flakes. Soluble pigment very slight. 



Milk: Slow digestion; no coagulation; slight grayish brown discoloration. 



Starch : Hydrolysis positive. 



Cellulose: Limited attack. 



Nitrate: Reduction positive or negative. 



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