762 



ORDER V. ACTINOMYCETALES 



Starch agar: Cream-colored growth with 

 brownish center; no aerial mycelium. 



Glucose agar: White aerial mycelium is 

 slowly formed. 



Yeast-glucose agar: Lichenoid, cream- 

 colored to brownish growth; white to gray- 

 ish aerial mycelium; soluble yellowish pig- 

 ment. 



Glucose broth: Flaky growth. 



Milk: Cream-colored to yellowish growth; 

 aerial mycelium thin, white. Rapidly pep- 

 tonized without previous coagulation. 



Potato: Lichenoid, cream-colored to 

 brownish growth, later becoming reddish 

 brown; aerial mycelium powdery white to 

 gray; no soluble pigment. 



Starch is weakly hydrolyzed. 



Esculin is attacked. 



Good growth on cellulose. 



Nitrites produced from nitrates. 



Aerobic. 



Optimum temperature, 35° C. 



Antagonistic properties: Strongly antag- 

 onistic. 



Source: Isolated from soil. 



Habitat: Soil. 



21. Streptomyces aureofaciens Duggar, 

 1948. (Ann. N. Y. Acad. Sci., 51, 1948, 177; 

 U. S. Patent 2,482,055, Sept. 13, 1949.) 



au.re.o.fa'ci.ens. L. neut.n. aurum gold; 

 L. part. adj. faciens producing; M.L. part, 

 adj. aureofaciens golden-making. 



Vegetative growth: Mycelium hyaline, 

 becoming yellow in 2 to 3 days, later golden 

 tan to tawny. 



Aerial mycelium: White, becoming brown- 

 ish gray to dark, drab-gray in 5 to 10 days. 

 Sporophores straight, flexuous; no spirals. 

 Spores spherical to ellipsoidal, longest di- 

 ameter 1.5 microns. 



Gelatin: No liquefaction. 



Agar: Good, light brownish growth. No 

 aerial mycelium. No soluble pigment. 



Asparagine-meat extract glucose agar: 

 Hyaline growth changing to orange-yellow. 

 Aerial mycelium abundant, white, changing 

 to deep gray or dark gray with tawny re- 

 verse. Faint yellowish soluble pigment. 



Milk: Limited, yellow-brown growth. No 

 coagulation or peptonization. 



Potato: Wrinkled, orange-yellow growth. 

 Color of plug unchanged. 



Antagonistic properties: Produces chlor- 

 tetracycline, an amphoteric compound 

 containing both nitrogen and non-ionic 

 chlorine, active against various bacteria, 

 rickettsiae and the larger viruses. 



Comments: The numerous natural and 

 induced variants of S. aureofaciens display 

 wide variations in color of vegetative growth 

 ranging from pale yellow to reddish brown 

 and even occasionally greenish depending 

 upon the composition of the nutrient sub- 

 strates and environmental conditions. The 

 color of aerial mycelia is influenced by 

 sporulation. Yellowish, soluble pigment 

 often not discernible. Loose spirals are in- 

 frequently encountered. 



Source: Isolated from soil. 



Habitat: Presumably soil. 



22. Streptomyces albidoflavus (Rossi- 

 Doria, 1891) Waksman and Henrici, 1948. 

 {Streptotrix (sic) albido-flava Rossi-Doria, 

 Ann. d. 1st. d'Ig. sper. d. Univ. di Roma, 1, 

 1891, 407; Waksman and Henrici, in Manual, 

 6th ed., 1948, 949.) 



al.bi.do.fla'vus. L. adj. albidus white; 

 L. adj. flavus yellow; M.L. adj. albidoflavus 

 whitish yellow. 



Description taken from Duche (Encyclo- 

 pMie Mycologique, Paris, 6, 1934, 294). 



Gelatin: Punctiform colonies with white 

 aerial mycelium on surface of liquid; no 

 soluble pigment; rapid liquefaction. 



Agar: Cream-colored growth covered with 

 fine white aerial mycelium; yellow soluble 

 pigment. 



Synthetic asparagine agar: Growth be- 

 comes rapidly covered with white aerial 

 mycelium, later becoming whitish yellow; 

 brown on reverse side; yellowish soluble pig- 

 ment. 



Tyrosine agar: Fine growth with orange- 

 yellow on reverse side; medium becomes 

 colored yellowish to yellowish rose. 



Synthetic asparagine solution: Long 

 branching filaments, 0.6 micron in diame- 

 ter. Thicker aerial mycelium producing 

 irregular spores; flaky growth dropping to 

 bottom of tube. Surface growth becomes 

 covered with yellowish white aerial myce- 

 lium; brownish on reverse side; soluble pig- 

 ment yellowish. 



Peptone solution: Rapid, much folded 



