SERIES AND SPECIES OF l JEN US STREPTOM\ < I S 



111 



Tab: i 20 

 son of cultural characteristics of four strains of Streptomyces California - at media 



Burkholdei ■ I 



suggested thai they be raised to the status 

 of a species within the S. griseus section. A 

 further study of this species points to its 

 identity to S. californicus, which lias pri- 

 ority in species designation. 



.">. Streptomyces chrysomallus (Lindenbein) 

 Waksman. These comprise strains which 

 produce actinomyein. Welsch et al. (1957) 

 studied 51 cultures of Streptomyces for their 

 susceptibility to seven actinophages; 13 

 of the strains produced actinomyein and 

 eight represented nonact inomycin-producing 

 strains of S. griseus. Certain actinomycin- 

 producing organisms, including the Linden- 

 bein culture of S. chrysomallus and a culture 

 of S. parvus, were considered to belong to 

 the S. griseus section. A del ailed study of the 

 actinomycin-producing organisms has re- 

 cently been made by Solovieva and Die- 

 lova (1960). 



Various other organisms belonging to the 

 S. griseus section are able to form at least two 

 other antibiotics. One of these, cyclohex- 

 imide, is active only againsl fungi, and 

 another, streptocin, is active againsl certain 



protozoan-like organisms. No detailed s1 udy 

 has as yet been made of these strains in an 

 effort to raise them to specie- status. 



There are also those strains of S. griseus 

 that produce no antibiotic at all, at leasl as 

 far as one is able to detect by available 

 methods. 



The streptomycin-producing strains of S. 

 griseus give rise readily to mutants. Two 

 such mutants have been reported: One was 

 a colorless form, producing no aerial myce- 

 lium, forming no streptomycin, and sensitive 

 to this antibiotic; Dulaney <l al. I L949) re- 

 ported, however, on a colorless mutanl that 

 produced streptomycin. The other was a 

 pigmented mutant, forming pink to vina- 

 ceous-colored subsl rate growth and an aerial 

 mycelium typical of S. griseus; 1 his mutant 

 formed no streptomycin but gave rise to 

 another antibiotic (rhodomycetin), which 

 was not active against gram-negative bac- 

 teria. According to Kutzner I I960), this 

 strain shows much similarity, on the basis of 

 phage sensitivity and other properties, to 

 S. californicus. A detailed study of degenera- 



