FAMILY ni. STREPTOMYCETACEAE 



797 



Linn. Soc. New So. Wales, 56, 1931, 257; 

 Waksman and Henrici, in Manual, 6th ed., 

 1948, 953.) 



hy.gro.scop'i.cus. Gr. adj. fiyynis moist; 

 Gr. noun scopiis watcher; M.L. adj. hygro- 

 scopicus detecting moisture or covered with 

 moisture. 



Vegetative growth: Hyphae 0.6 to 0.8 mi- 

 cron in diameter. 



Aerial mycelium: Hyphae long, tangled, 

 branched, 0.8 to 1.0 micron in diameter. 

 Spirals numerous, sinistrorse, narrow, usu- 

 allj^ short, only 1 or 2 turns, closed, typically 

 situated as dense clusters on the main stems 

 of the aerial hyphae. Spores ellipsoidal, 

 0.8 to 1.0 by 1.0 to 1.2 microns. 



Gelatin: Slow liquefaction. No pigment 

 produced. 



Agar: Good growth; raised, wrinkled, 

 glossy, cream-colored; later yellowish gray 

 with yellowish brown reverse. Occasionally 

 a scant white aerial mj^celium. 



Sucrose agar: Good to abundant growth. 

 Vegetative mycelium heavy, superficially 

 spreading, folded, glossy surface, white to 

 cream-colored, later sulfur-yellow to yellow- 

 ish gray, with golden to light orange reverse. 

 Soluble pigment of the same color. Aerial 

 mycelium scant, thin, white or absent. 



Glucose agar: Good growth; granulated, 

 cream-colored to straw-yellow, later dull 

 chrome-yellow to brownish orange. Aerial 

 mycelium thin, smooth, dusty, white to pale 

 yellowish gray, after 1 or 2 weeks more or 

 less abundantly interspersed with small, 

 moist, dark violet-gray to brownish patches 

 which gradually spread over the whole sur- 

 face. Light yellow soluble pigment. 



Potato: Fair growth. Vegetative my- 

 celium raised, wrinkled, cream-colored, 

 later yellowish gray to dull brownish. 

 Aerial mycelium absent or trace of white. 



Milk: Completely digested in 3 to 4 weeks 

 at 30° C. without any previous coagulation. 

 The reaction becomes faintly acid (pH 6.0 

 or less). 



Sucrose is inverted. 



Starch is hydrolj^zed. 



Cellulose is decomposed readily by some 

 strains. 



Nitrates not reduced with sucrose as 

 source of energy. 



Antagonistic properties: Positive. 



Distinctive character: In this species, the 

 aerial mycelium (which in other actinomy- 

 cetes is strikingly hydrophobic) on certain 

 media (glucose or glycerol asparagine agar) 

 becomes moistened and exhibits dark, glis- 

 tening patches. These patches, when 

 touched with a needle, prove to be a moist, 

 smeary mass of spores. This characteristic 

 feature is not equally distinct in all strains. 



Source: Seven strains were isolated from 

 soils. 



Habitat: Soil. 



100. Streptomyces longisporoflavus 



(Krassilnikov, 1941) Waksman, 1953. (Ac- 

 tinomyces longisporus flavus Krassilnikov, 

 Guide to the Actinomycetes, Izd. Akad. 

 Nauk, U.S.S.R., Moskau, 1941, 30; Waks- 

 man, in Waksman and Lechevalier, Actino- 

 mycetes and Their Antibiotics, Baltimore, 

 1953, 94.) 



lon.gi.spo.ro.fla'vus. L. adj. longus long; 

 Gr. noun spora a seed; M.L. fem.n. spora a 

 spore; L. adj. flavus 3'ellow; M.L. adj. 

 longisporoflavus long-spored, yellow. 



Vegetative growth: Yellow, lemon-yellow 

 or dirty yellow, seldom golden yellow 

 colonies. Pigment not soluble. Some strains 

 have a greenish tinge, depending on the 

 composition of the medium. 



Aerial mycelium: Well developed, velvety, 

 whitish yellow to brownish yellow. Sporo- 

 phores produce long, open spirals. Spores 

 cylindrical or elongated, 1.0 to 1.5 by 0.7 

 microns; some with rounded ends and swol- 

 len in center. 



Gelatin: Liquefaction in 10 to 15 days. 



Milk: Coagulated; slowly peptonized. 



Sucrose not inverted. 



Starch is weakly hj'drolyzed. 



No growth on cellulose. 



Nitrites actively produced from nitrates. 



Antagonistic properties: Weakly antago- 

 nistic. 



Source: Isolated from soil. 



Habitat: Soil. 



101. Streptomyces candidus (Krassil- 

 nikov, 1941) Waksman, 1953. (Actinomyces 

 candidus Krassilnikov, Guide to the Actino- 

 mycetes, Izd. Akad. Nauk, U.S.S.R., Mos- 

 kau, 1941, 49; Waksman, in Waksman and 

 Lechevalier, Actinomycetes and Their 



