HI SCREPTION OF SPECIES OF STREPTOMYCES 



183 



yellowish. Aerial mycelium abundant, white. 

 No soluble pigment. 



Glucose-yeasi extract-peptone agar: 

 Growth yellowish bo buff. Aerial mycelium 

 white to gray. No soluble pigment. 



Potato agar: Growth smooth, yellowish- 

 brown. Aerial mycelium while to bluish- 

 gray. Soluble pigmenl at first absent, later 

 dark. 



Gelatin: Growth on surface good. Ae.ial 

 mycelium white. Rapid liquefaction. Soluble 

 pigmenl dark brown. 



Potato: Growth folded, brown to black. 

 No aerial mycelium. 



Milk: Growth moderate. No coagulation; 

 no peptonization. 



Antagonistic properties: Produces anti- 

 biotic B-mycin, active againsl cocci, gram- 

 positive bacteria, and mycobacteria. 



Habitat : Soil. 



Remarks: This is one of the organisms 

 thai can be either melanin-negative (nutri- 

 ent agar, yeast extract agar) or melanin- 

 positive (gelatin, potato agar). 



33. Streptomyces brasiliensis (Spencer, 

 1921) Waksnian (Spencer, 1-:. P. Botan. 

 (iaz. 72:285-287, 1921). 



Morphology: Aerial mycelium forms 

 straight, branched sporophores. Spores borne 

 in chains on free ends of hyphae, oblong, 

 l.ti. by 0.8 m- 



Sucrose nitrate agar: Growth at first 

 white; after 10 days pale pinkish-buff. Aerial 

 mycelium white and dense. No soluble pig- 

 ment . 



Glucose-asparagine agar: Growth luxuri- 

 ant, color same as on sucrose nitrate agar, 

 thallus conspicuously zonated. Aerial myce- 

 lium powdery, white to pale pinkish-buff. No 

 soluble pigment. 



Glycerol malate agar: Growth spreading 

 and not zonated, bordered by submerged 

 mycelial bands of varying width, pearl- 

 white. Aerial mycelium short, loose, and 

 pearl-white. 



Potato: Growth vigorous, crumpled, pale 



pinkish-buff. Aerial mycelium abundant, at 

 first white, later pale pinkish-buff. No solu- 

 ble pigment. Melanin-negative. 



\'ut plugs: Growth vigorous, pale pinkish- 

 buff. Aerial mycelium powdery, white. 

 Medium not completely destroyed, but 

 much shrunken and blackened. 



Gelatin: Rapid liquefaction. No soluble 

 pigment. 



Milk: Papid coagulation and peptoniza- 

 tion. 



Habitat: Parasitic on kernels of Brazil 

 nuts. 



Remarks: This Streptomyces species is to 

 be distinguished from Xocurdia brasiliensis, 

 a pathogenic organism. 



34. Streptomyces cacaoi (Waksman, 1932) 

 Waksman and Benrici, 1948 (Waksman, S. 

 A. In Bunting, P. H. Ann. Appl. Biol. 19: 

 515-517, 1932). 



Morphology: Sporophores long; spirals 

 long and open, not compact. 



Sucrose nitrate agar: Growth thin, yel- 

 lowish, later turning reddish-brown. Aerial 

 mycelium light gray to mouse-gray, with 

 white edge. Xo soluble pigment. 



Nutrient agar: Growth brown, covered 

 with tiny patches of ivory-colored aerial 

 mycelium. 



Potato: Growth abundant, brownish. 

 Aerial mycelium white to mouse-gray. Mel- 

 anin-negative. 



Gelatin: Growth flocculent. Xo aerial 

 mycelium. Liquefaction rapid. Xo soluble 

 pigment. 



Nitrate reduction: Limited. 



Production of IBS: Negative. 



Antagonistic properties: Certain strains 

 produce an antibiotic designated as cacao- 

 mycetin. 



Source: Three strains were isolated from 

 cacao beans in Nigeria. They showed -light 

 differences, the foregoing description being 

 based on one strain. 



Remarks: Strong proteolytic enzymes, 

 strong diastatic action, no sugar or dextrin 



