944 



MANUAL OF DETERMINATIVE BACTERIOLOGY 



less growth. Aerial mycelium thin, gray, 

 powdery, becoming cinnamon drab. 



Starch agar : Thin, transparent, spread- 

 ing growth. 



Glucose agar: Spreading, light orange 

 growth, raised center, hyaline margin. 



Plain agar : Restricted, gray grov.th. 



Glucose broth: Thin, brownish ring; 

 flaky sediment. 



Litmus milk: Black ring. No coagula- 

 tion. Peptonization doubtful. 



Potato: Abundant, wrinkled, brown 

 growth, becoming black. 



Nitrites produced from nitrates. 



Soluble brown pigment formed. 



Starch is hydrolyzed. 



Aerobic. 



Optimum temperature 25°C. 



Source : Isolated many times from a 

 variety of soils. 



Habitat: Soil. 



24. Streptomyces erythrochromogenes 



(Krainsky) comb, no v. (Actinomyces ery- 

 throchromogenes Krainsky, Cent, f . Bakt., 

 II Abt., Jtl, 1914, 662; Waksman and Cur- 

 tis, Soil Science, /, 1916, 112.) From 

 Greek, producing a red color. 



Conidia oval, about 2.0 microns long. 



Gelatin colonies: Slow growth. 



Gelatin stab: Liquefied. A soluble 

 brown pigment formed. 



Plain agar: Brown soluble pigment. 

 White aerial mycelium. 



Ca-malate agar : Colonies circular, with 

 grayish-white margined aerial mycelium. 



Glucose agar: Red pigment formed. 



Starch agar : A soluble rose pigment on 

 old cultures. 



Glucose broth: Abundant growth. 

 Floating colonies, later a pellicle is 

 formed. Brown soluble pigment. 



Potato: Gray aerial mycelium. 

 Medium colored black. 



Nitrates show slight reduction. 



Weakly diastatic. 



No proteolytic enzyme formed. 



No growth in cellulose. 



Aerobic. 



Optimum temperature 30°C. 



Source : Soil and roots of Alnus (alder). 

 Habitat: Soil. 



25. Streptomyces lavendulae (Waks- 

 man and Curtis) comb. nov. {Actino- 

 myces lavendulae Waksman and Curtis, 

 Soil Science, 1, 1916, 126.) FromM. L., 

 lavender. 



Hyphae coarse, branching. Spirals 

 close, 5 to 8 microns in diameter. Conidia 

 oval, 1.0 to 1.2 by 1.6 to 2.0 microns. 



Gelatin stab : Creamy to brownish sur- 

 face growth. Liquefied. 



Synthetic agar: Thin, spreading, color- 

 less growth. Aerial mycelium cottony, 

 white, becoming vinous-lavender. 



Starch agar : Restricted, glistening, 

 transparent growth. 



Plain agar : Gray, wrinkled growth. 



Glucose broth: Abundant, flaky sedi- 

 ment. 



Litmus milk: Cream-colored ring. No 

 coagulation; peptonized, with strong al- 

 kaline reaction. 



Potato: Thin, wrinkled, cream-colored 

 to yellowish growth. 



Nitrites produced from nitrates. 



Soluble brown pigment formed. 



Starch is hydrolyzed. 



Aerobic. 



Optimum temperature 37°C. 



Certain strains of this organism pro- 

 duce antibiotics. One such antibiotic, 

 designated as streptothricin, is active 

 both in vitro and in vivo against various 

 Gram-positive and Gram-negative bac- 

 teria, fungi and actinomycetes (Waks- 

 man and Woodruff, Proc. Soc. Exp. Biol. 

 I\Ied., 49, 1942, 207; Waksman, Jour. 

 Bact., 46, 1943, 299). 



Source : Isolated once from orchard soil . 



Habitat: Soil. 



26. Streptomyces reticuli (Waksman 

 and Curtis) comb. nov. (Actinomyces 

 reticuli Waksman and Curtis, Soil Sci- 

 ence, 1, 1916, 118.) From Latin reticulum, 

 a small net. 



Mycelium in whorls; spirals formed on 



