FAMILY III. STREPTOMYCETACEAE 



781 



against various Gram-positive and Gram- 

 negative bacteria, rickettsiae and the larger 

 viruses. 



Comment : The type culture of this species 

 was found in the culture bureau of Parke, 

 Davis and Company, Detroit, No. 04745. A 

 culture of this organism described by 

 Umezawa and Maeda as a variety of Strep- 

 tomyces phaeochromogenes is regarded by 

 Waksman as identical with this species. 

 (See Waksman, in Waksman and Leche- 

 valier, Actinomycetes and Their Anti- 

 biotics, Baltimore, 1953, 73.) 



Source: Isolated from soil in mulched field 

 near Caracas, Venezuela. 



Habitat: Soil. 



62. Streptomyces virgiiiiae Grundy et 

 al., 1952. (Grundy, Whitman, Rdzok, Hanes 

 and Sylvester, Antibiotics and Chemo- 

 therapy, 2, 1952, 399.) 



vir.gi'ni.ae. M.L. noun Virginia Virginia; 

 M.L. gen. noun virginiae of Virginia. 



Vegetative growth: Cream-colored to 

 light brown on complex media; soluble, 

 light brown, diffusible pigment. On syn- 

 thetic media white to cream-colored growth 

 with pink or grayish lavender aerial myce- 

 lium. Undulating mycelium about 1 micron 

 in diameter with short, thinner side 

 branches. 



Aerial mycelium: Long, grayish pink or 

 lavender aerial hj-phae. Most of the sporu- 

 lating hyphae straight, occasionally a spiral 

 is observed at or near the tip of the hypha. 

 Spirals vary from tightly closed knots to 

 loose, open spirals. Spores cylindrical, 0.75 

 to 1.0 by 1.1 to 1.5 microns. 



Gelatin: Gray to brownish surface pel- 

 licle. Aerial mycelium thin, white. Soluble 

 brown pigment extending as far as liquefied 

 zone. Slow liquefaction. 



Agar: Sparse, white growth, turning 

 cream-colored. White aerial mycelium, 

 turning light grayish lavender when sporu- 

 lation occurs. No soluble pigment. 



Synthetic glucose agar: Sparse, cream- 

 colored growth. Aerial mycelium light 

 grayish lavender. No soluble pigment. 



Glucose asparagine agar: Sparse, cream- 

 colored growth. No aerial mycelium. No 

 sporulation. No pigmentation. 



Ca-malate agar : Abundant, cream-colored 

 growth. White aerial mycelium becoming 

 tinged with grayish lavender. No soluble 

 pigment. 



Starch agar: Thin colorless growth with 

 aerial mycelium rose- to lavender-colored. 



Oatmeal agar: Abundant, cream-colored 

 growth, turning golden brown. Abundant 

 light rose aerial mycelium, turning lavender 

 and gray. Soluble pale j-ellow pigment, 

 turning light brown. 



Broth: Thin, cream-colored surface ring; 

 a few flakes on bottom. Soluble brownish 

 pigment. 



Milk: Brown growth. Milk becomes dark 

 gray-brown or black. Not coagulated; 

 slowly peptonized. 



Potato: Abundant, spreading, brownish 

 growth. Aerial mycelium grayish lavender. 

 Browning of potato. 



Starch is hydrolyzed. 



Glucose, mannose, galactose, maltose, 

 starch, glycerol, sodium acetate and so- 

 dium citrate are utilized. Xylose, lactose, 

 sucrose, mannitol, sorbitol and potassium 

 sodium tartrate are not utilized. 



Nitrites weakly produced, if at all, from 

 nitrates. 



Optimum temperature, between 28° and 

 30° C. 



Antagonistic properties: Produces acti- 

 thiazic acid. 



Source: Isolated from soil near Roanoke, 

 Virginia. 



Habitat: Soil. 



63. Streptomyces reticuli (Waksman 

 and Curtis, 1916) Waksman and Henrici, 

 1948. (Actinomyces reticuli Waksman and 

 Curtis, Soil Sci., 1, 1916, 118; Waksman and 

 Henrici, in Manual, 6th ed., 1948, 944.) 



re.ti'cu.li. L. dim. noun reticulum a small 

 net; L. gen. noun reticuli of a small net. 



Aerial mycelium: Whorls; spirals formed 

 on glucose agar are sinistrorse. Conidia 

 spherical, 1.0 to 1.4 microns in diameter. 



Gelatin stab: Liquefaction, with small, 

 brown flakes. 



Agar: Gray, wrinkled growth, becoming 

 brownish. 



Synthetic agar: Colorless growth, with 



