Potato: Lichenoid, cream-colored to brownish growth. No aerial mycelium. No soluble pigment. Starch is actively hydrolyzed. Nitrites not produced from nitrates. Source: Isolated from the sputum of a patient with chronic lung disease. Habitat: Unknown. 85. Streptoinyces griseus (Krainsky, 1914) Waksman and Henrici, 1948. {Actino- myces griseus Krainsky, Cent. f. Bakt., II Abt., 41, 1914, 662; Waksman and Henrici, in Manual, 6th ed., 1948, 948; also see Waks- man, Reilly and Harris, Jour. Bact., 56, 1948, 259.) gri'se.us. M.L. adj. griseus gray. Vegetative growth: Colonies smooth or folded, colorless, later turning olive-buff. Aerial mycelium: Abundant, powderj^, water-green. Sporophores produced in tufts. Spores spherical to ellipsoidal, 0.8 by 0.8 to 1.7 microns. Agar: Abundant, cream-colored, almost transparent growth. Aerial mycelium pow- dery, white to light gray. No soluble pig- ment. Gelatin stab: Greenish yellow or cream- colored surface growth with brownish tinge. Rapid liquefaction. Synthetic agar: Thin, colorless, spread- ing growth, becoming olive-buff. Aerial mycelium thick, powdery, water-green. Starch agar: Thin, spreading, transparent growth. Glucose agar: Growth elevated in center, radiate, cream-colored to orange, erose margin. Glucose broth: Abundant, 3-ellowish pel- licle with greenish tinge, much folded. Litmus milk: Cream-colored ring; coagu- lated with rapid peptonization, becoming alkaline. Potato: Yellowish, wrinkled growth cov- ered with white, powderj^ aerial mycelium. The pigment formed is not soluble. Starch is hydrolyzed. Nitrites produced from nitrates. Aerobic. Optimum temperature, 37° C. Antagonistic properties: Strongly antago- nistic. DifYerent strains of this organism produce different antibiotics. One of these, streptomycin, is active against a large num- ber of bacteria and actinomycetes but not against fungi and viruses. Some strains pro- duce grisein. Others form candicidin. Distinctive characters: This species is dis- tinguished by Waksman from Streptomyces globisporus (No. 3) primarily on the basis of the yellow-green to gray color of the aerial mycelium on most media, and on the ability to coagulate milk and to hydroh'ze starch rapidly. Comments: The original de.scription of this organism by Krainsky (op. cit., 1914, 662) mentions spiral formation in the sporo- phores; the cultures subsequently isolated and described by Waksman and Curtis {op. cit., 1916, 119) and Waksman, Reilly and Harris {op. cit., 1948, 259) were not shown to exhibit spiral forms. In other characteri.stics these cultures resembled the original description. The description of Streptomyces griseus presented here is based largely on the description of the culture isolated by Waks- man and Curtis. Waksman does not feel that the differences among these various isolates are sufficient to justify separation into more than one species. Krassilnikov (Guide to the Bacteria and Actinomj'cetes, Izd. Akad. Nauk, U.S.S.R., Moskau, 1949, 93 and 98) regards the organ- ism isolated and described by Krainsky as different from the organisms isolated later by Waksman et al., the distinction being made on the appearance of the sporophores. Krassilnikov regards the organisms exhibit- ing spiral formation as Actinomyces griseus Krainsky; those without spiral formation as Actinomyces globisporus Krassilnikov. The streptomycin-producing strain is re- garded as a subspecies of the latter species rather than of the former. Source: Isolated from garden soil; later from soils, river muds and the throat of a chicken. Habitat: Presumably soil. 86. Streptomyces longissimus (Kras- silnikov, 1941) Waksman, 1953. {Actinomyces longissimus Krassilnikov, Guide to the Actinomycetes, Izd. Akad. Nauk, U.S.S.R., Moskau, 1941, 38; Waksman, in Waksman and Lechevalier, Actinomj^cetes and Their Antibiotics, Baltimore, 1953, 87.)
