22S 

 200 



THE ACTIXOMYCETES, Vol. I 



RESIDUAL 

 GLUCOSE 96 



C 



200 



175 



150 



125 





z 



100 u 



> 



o 



z 



h- 

 u 

 < 



75 



50 



25 



^0 



10 



DAYS 



FiGTRE 86. Utilization of glucose by <S. a/i;j6io//fus for growth and actinomycin production: A A = 



dry weight of mycelium in mg per 100 ml of medium; X X = i:)ercentage of residual glu- 

 cose; O O = actinomycin produced, fig/m\ of medium (Reproduced by special permission from: 



Katz, E., Pienta, P., and Sivak, A. Appl. Microbiol. 6: 237, 1958.) 



Numerous comprehensive re\'iews have 

 been pubhshed on the production of antibi- 

 otics by actinomycetes (Waksman ct al., 

 194(); Benedict, 1953; Krassihiikov, 1950; 

 Waksman and Lechevaher, 1958). 



Antimicrobial Spectra 



Differences in the range of antimicrobial 

 activities of \ari()us antibiotics are both 

 (iuantitati\-e and ([Ualitnt i\<' in na1ur(\ The 



antimicrobial spectrimi of each antibiotic is 

 so characteristic in nature, when determined 

 imder standard conditions and with standard 

 test organisms, that it can be used for the 

 determination of its particular specificity. 

 The antibiotics can be grouped not only on 

 the basis of their chemical properties, l)ut 

 also upon the basis of tlie specificity of their 

 corresponding spectra. 



Streptomycin, streptothricin, and neomy- 



