50. Streptoniyces viridoflavus Waks- man and Taber, 1953. (Waksman and Taber, in Waksman and Lechevalier, Actinomy- cetes and Their Antibiotics, Baltimore, 1953, 66.) vi.ri.do.fla'vus. L. adj. viridis green; L. adj. flavus yellow; M.L. adj. viridoflavus greenish yellow. Vegetative growth: Abundant, lichenoid growth on most media, j^ellow-green, turn- ing olive-green to almost brown. Soluble pigment variable. Hyphae on surface of agar 0.7 micron in diameter; in shake flasks, 0.7 to 0.8 micron; some submerged hyphae thicker, reaching 1.6 microns in diameter. Single spores formed at end of submerged sporulating lateral branches. Spores form early, germinate readily, even while ap- parently attached to hyphae. Aerial mycelium: Hyphae formed in fas- cicles, greenish yellow, turning gray. Tends to lose ability to produce aerial mycelium. Tufts of hyphae with some curling of tips produced on certain media (glucose-aspara- gine agar). On glucose-asparagine agar, spores produced in chains in whorls. Spores not formed on nutrient or glucose-nutrient agar. Gelatin: Limited growth in form of sur- face ring, canary-yellow. No pellicle. Solu- ble brown to dark brown pigment; ability to produce pigment may be lost on cultiva- tion. Slight liquefaction. Agar: Thin, moist, gray to light green, isolated colonies with green to almost bluish tinge at bottom of slant where colonies are confluent. White to gray, non-sporulating aerial mycelium appearing much later. No soluble pigment. Synthetic agar: Limited, cream-colored to yellowish green growth. Generally no aerial mycelium. Hyphae penetrate deep into agar. No soluble pigment. Glucose asparagine agar: Moist, flat, yel- low to yellow-green colonies growing deep into medium. Aerial hyphae frequently abundant, grayish yellow to sulfur-yellow, later overgrown by white sporulating hy- phae. May produce a soluble, faint yellow pigment. Yeast-glucose agar: Heavy lichenoid growth, dark brown to olive-green. Aerial hyphae pale to grayish yellow to greenish yellow, becoming gray with age. Soluble grown pigment. Glucose-nutrient agar: Heavy lichenoid growth, yellowish brown to olive-brown. Yellowish to gray aerial hyphae are abund- ant and appear later, covering the whole surface of growth with a mat. May produce a soluble brownish pigment. Broth: Colorless clumps of growth on bottom of container. Soluble brown pig- ment; ability to produce pigment may be lost on cultivation. Milk: Light yellow to brown surface ring. Not coagulated, gradually peptonized. Potato: Lichenoid, brownish to greenish yellow to dark olive-green growth. Aerial hyphae absent or formed as thin, yellowish layer on drier portions of growth. May pro- duce a soluble dark brown pigment. Starch is actively hydrolyzed. Limited growth on cellulose; cellulose not decomposed. Carbon sources: With yeast extract-min- eral agar there was no growth over con- trol on sucrose, lactose or rhamnose; good growth on mannose and glucose. Antagonistic properties: Produces anti- biotic substances, one of which is candi- cidin-like material. Comments : Several strains of this organ- nism have been isolated. They differ in their pigmentation on gelatin and in the relative abundance of aerial mycelium. Source: Isolated from soil. Habitat: Soil. 51. Streptoniyces globosus (Krassilni- kov, 1941) Waksman, 1953. (Actinomyces globosus Krassilnikov, Guide to the Acti- nomycetes, Izd. Akad. Nauk, U.S.S.R., Moskau, 1941, 58; Waksman, in Waksman and Lechevalier, Actinomycetes and Their Antibiotics, Baltimore, 1953, 68.) glo.bo'sus. L. adj. globosus round, spheri- cal. Vegetative growth: Dark brown colonies producing brown pigment which diffuses into medium. Aerial mj'celium: Dark gray, fine velvety. Sporophores straight, short. Spores spheri- cal. Gelatin: Weak liquefaction. Milk: Peptonized.
