FAMILY STKEPTOMYCETACEAE 



943 



Glucose broth: Dense, solid ring, 

 brownish, becoming dark green. 



Litmus milk: Dark brown surface 

 growth; coagulated; peptonized, with 

 faintly alkaline reaction. 



Potato : Abundant, gray-brown growth. 



Nitrites produced from nitrates. 



Soluble brown pigment formed. 



Starch is hydrolyzed. 



Aerobic. 



Optimum temperature 37 °C. 



Habitat : Soil . 



21. Streptomyces purpeochromogenus 



(Waksman and Curtis) covih. nov. {Ac- 

 tinomyces 'purpeochromogenus Waksman 

 and Curtis, Soil Science, 1, 1916, 113.) 

 From Latin, purple and Greek, producing 

 color. 



Branching nn^celium and hyphae with 

 few imperfect spirals. Conidia spheri- 

 cal, 0.75 to 1.0 micron in diameter. 



Gelatin stab : Slow, brownish surface 

 growth. Slow liquefaction. 



Synthetic agar: Slow, restricted, 

 smooth, gray growth, becoming brown 

 with purplish tinge; center raised. 

 Margin yellow. 



Starch agar : Smal 1 , dark brown colonies . 



Glucose agar: Abundant, restricted, 

 gray growth, becoming brown to dark 

 brown. 



Plain agar: Gray to brownish growth, 

 becoming dark brown, almost black. 



Glucose broth : Slight, flaky sediment. 



Litmus milk : Dark-brown ring ; coagu- 

 lated; slowly peptonized, with faintly 

 alkaline reaction. 



Potato: Restricted, orange to orange - 

 red growth . 



Nitrites not produced from nitrates. 



Soluble dark brown pigment formed. 



Starch shows slight hydrolysis. 



Aerobic. 



Optimum temperature 25°C. 



Source : Isolated once from California 

 adobe soil . 



Habitat : Soil. 



22. Streptomyces phaeochromogenus 

 (Conn) comb. nov. {Actinomyces pheo- 

 chromogenus (sic) Conn, N. Y. State 

 Agr. Exp. Sta. Tech. Bull. No. 60, 1917, 

 16.) From Greek, producing a brown 

 color. 



Branching filaments and hyphae, 

 spirals narrow, open, elongated, sinis- 

 trorse . 



Gelatin stab : Abundant, spreading, 

 cream-colored surface growth, becoming 

 brown. Slow liquefaction. 



Synthetic agar: Colorless growth, be- 

 coming brown to almost black. Aerial 

 mycelium abundant, white with brownish 

 shade. 



Starch agar: Spreading, brownish 

 growth, becoming brown. 



Glucose agar : Restricted, much folded, 

 brown growth . 



Plain agar : Thin, cream-colored growth, 

 beconaing gray. 



Glucose broth : Dense, wrinkled 

 pellicle. 



Litmus milk: Dark, almost black ring; 

 coagulated, with slow peptonization, 

 faintly alkaline reaction. 



Potato : Brown to almost black growth. 



Nitrites produced from nitrates. 



Soluble brown pigment formed. 



Starch is hydrolyzed. 



Aerobic. 



Optimum temperature 25''C. 



Source : Isolated from soil. 



Habitat : Soil. 



23. Streptomyces aureus (Waksman 

 and Curtis) comb. nov. {Actinomyces 

 a7ire«.s Waksman and Curtis, Soil Science, 

 1, 1916, 124; not Actinomyces aurea Ford, 

 Textb. of Bact., 1927, 220.) From Latin 

 aureus, golden. 



Mycelium shows numerous spirals. 

 Conidia spherical to oval, 0.6 to 1.0 by 

 0.8 to 1.4 microns. 



Gelatin stab : Fair, cream-colored sur- 

 face growth, becoming brown, spreading. 

 Liquefied. 



Synthetic agar : Thin, spreading, color- 



