Source: Presumably soil. Habitat: Soil. 10. Streptomyces violaceus (Rossi- Doria, 1891, emend. Krassilnikov, 1941) Waksman, 1953. {Streptotrix (sic) violacea Rossi-Doria, Ann. d. Inst. d'Ig. sper. d. Univ. di Roma, /, 1891, 411; Actinomyces violaceus Gasperini, Cent. f. Bakt., 15, 1894, 684; Krassilnikov, Guide to the Actinomyce- tes, Izd. Akad. Nauk, U.S.S.R., Moskau, 1941, 15; Waksman, in Waksman and Leche- valier, Actinomycetes and Their Antibi- otics, Baltimore, 1953, 43.) vi.o.la'ce.us. L. adj. violaceus violet- colored. Vegetative growth: Well developed, non- septated; readily breaks up in old cultures. Lichenoid colonies at first red, then becoming dark blue and finally purple-violet. Some cultures produce fat droplets in the colony, pigmented red or purple. Aerial mycelium: Produced only poorly or not at all; some substrates, such as cellu- lose, paraffin or fats, favor its formation. Aerial hyphae long, straight, seldom branch- ing and also short-branched. Sporophores forming open spirals, sinistrorse curvatures. Spores spherical and ellipsoidal. Gelatin: Slow liquefaction. Synthetic agar: Diffusible pigments which become purple-violet to dark violet. Milk: Not coagulated; slowly peptonized. Sucrose rapidly inverted. Starch is weakly hydrol.yzed. Poor or no growth on cellulose. No evidence of nitrate reduction by most strains; a few strains give a positive nitrite reaction. Optimum temperature, between 25° and 30° C. Antagonistic properties: Exerts strong antagonistic effect upon various bacteria. Source: Isolated from air and water. Habitat: Unknown. 11. Streptomyces verne (Waksman and Curtis, 1916) Waksman and Henrici, 1948. {Actino7nyces verne Waksman and Curtis, Soil Sci., 1, 1916, 120; Waksman and Hen- rici, in Manual, 6th ed., 1948, 936.) ver'ne. Etymology uncertain. Filaments with close branching of the hyphae. Capacity to produce aerial myce- lium lost on cultivation. Gelatin stab: Small, cream-colored col- onies. Rapid liquefaction. Agar: Small, grayish colonies with de- pressed center, becoming wrinkled. Synthetic agar: Abundant, spreading, wrinkled, elevated, glossy, yellowish growth, becoming brownish, lichenoid mar- gin. Starch agar: Scant, brownish, restricted growth. Glucose agar: Abundant, much folded growth, center raised, gray with purplish tinge, entire. Glucose broth: Slightly flaky sediment. Litmus milk: Pinkish brown ring; coagu- lated; peptonized, with alkaline reaction. Potato: Cream-colored growth, becoming gray, wrinkled. Soluble brown pigment formed. Soluble green pigment produced when freshly iso- lated. Starch is hydrolyzed. Nitrites produced from nitrates. Aerobic. Optimum temperature, 37° C. Antagonistic properties: Limited activity against some bacteria. Source: Isolated once from upland Cali- fornia soil. Habitat: Soil. 12. Streptomyces viridans (Krassilni- kov, 1941) Waksman, 1953. (Actinomyces viridans Krassilnikov, Guide to the Actino- mycetes, Izd. Akad. Nauk, U.S.S.R., Mos- kau, 1941, 33; Waksman, in Waksman and Lechevalier, Actinomj'cetes and Their Anti- biotics, Baltimore, 1953, 44.) vi'ri.dans. L. part. adj. viridans green- making. Vegetative growth: Green to brown-green colonies. Aerial mycelium: Dark gray, olive-colored or gray-green, velvety, covering the whole colony. Sporophores long, spiral-shaped. Spores cylindrical. Gelatin: Rapid liquefaction. Agar: Brown-green growth. Soluble brown substance produced. Synthetic agar: Green colonies. Soluble green pigment produced.
