THERMOPHILIC A.CTINOMYCETES 



305 



Aerial mycelium chalk-white. Cultures are 

 thermophilic, facultatively aerobic. Aerial 

 spores produced in 3 to 4 days in hanging 

 drops. Spores formed on simple or branched 

 sporophores. Spores oval, later round. 



Sucrose nitrate agar: Growth colorless. 

 Aerial mycelium moderate. 



Glycerol-asparagine agar: Growth abun- 

 dant, yellow. Aerial mycelium produced. 



Nutrient agar: Growth good, yellow. 

 Aerial mycelium thick. 



Potato: Growth yellow, partly covered 

 with aerial mycelium. Soluble pigment light 

 brown. 



Starch: No hydrolysis. 



Nitrate reduction: Weak. 



Milk: Unchanged in 16 days. 



Gelatin: Not liquefied. 



Temperature: Optimum growth at .">()('. 

 Limited growth at 28 and 65°C. 



Habitat: Fresh cow manure and manure 

 compost. 



2. Thermomonospora fusca (Waksman et 

 ill., 1939) Henssen (Henssen, A. Arch. 

 Mikrobiol. 26: 373-414, 1957). 



Morphology: Aerial hyphae 20 to 30 /j, 

 long. Spores round 1.5 to 2.0 p.. Since the 

 Spores are not produced on the substrate 

 mycelium as in Micromonospora, but ex- 

 clusively on the aerial mycelium, the species 

 was transferred from Micromonospora fusca 

 to Thermomonospora fusca. The branching 

 of the substrate mycelium is monopodial. 

 The hyphae are long, straight, and form 

 straight side branches. The branching is so 

 characteristic, as compared to all the other 

 thermophilic species, that this species can 

 easily l>e recognized. The aerial mycelium 

 is colored brown (Fig. 60). 



Sucrose nitrate agar: Growth at 28°C 

 deep gray; at 50°C, growth is dark brown to 

 violet. Aerial mycelium gray to lavender. 

 Soluble pigment brown. 



( relatin: Liquefied. 



Potato: Growth brown-colored. No aerial 

 mycelium. Soluble pigment black. 



Milk: No coagulation; slight peptoniza- 

 tion. 



Habitat: Horse manure. 



Starch: Hydrolysis. 



Nitrate reduction: Slight. 



Cellulose: Growth good. 



Temperature: Growth and aerial myce- 

 lium formation are good at 50 65°C. 



3. Thermomonospora lineata Henssen, 

 1957 (Henssen, A. Arch. Mikrobiol. 26: 373- 

 414, 1957). 



Morphology: Sporophores straight, 50 to 

 SO p. long; spores round, 1.5 to 2.0 //• Spore 

 chains hairy or clumpy (Pig. 61). 



Culture was isolated on nutrient agar but 

 was not obtained in pure state. Aerial hy- 

 phae mostly branched. Spores produced on 

 simple or branched sporophores. Substrate 

 hyphae monopodial and branched. Hyphae 

 are not as long as in the case of T. fusca. 

 Side branches are more compact. 



Optimum growth: 50-60°C. 



Habitat : Composted slice]) manure. 



Genus Thermopolyspora 



( irowth on agar media colorless to yellow. 

 Substrate mycelium not septated. Aerial 

 mycelium limited, white. Aerial hyphae not 

 branched, developing in the form of side or 

 terminal branches of the substrate hyphae. 

 Spores produced in short chains on un- 

 branched sporophores. Spore formation 

 acropetal. Spore chains unbranched, straight, 



