124 



THE ACTIX()AIYCU:TES, Vol. I 



12 



z<. 36 A8 eo 



TIHE , HOURS 



Fi(it KK 5S. (Irowtli and chlortcMriicyclinc for- 

 mation l)y .S. (iiireofaciens (Reproduced from; 

 Biffi, (!. ct al. Appl. Mierobiol. 2: 289, 1954). 



be broken down by 25 per cent of all actino- 

 mycete strains freshly isolated from soil. The 

 presence of yeast extract and the use of am- 

 monium sulfate in place of nitrate as a 

 source of nitrogen gi'^'ii^ly facilitate this re- 

 action. 



Numerous other studies have been re- 

 ported on the utilization of various carbo- 

 hydrates and their derivatives by different 

 actinomycetes, as exemplified in the work of 

 Anderson et al. (Table 25). 



Mariat (1958) studied the utilization of 15 

 carbon compounds in synthetic media by 

 various path()j>;enic strains of nocardia and 

 streptomyces. Glucose was utilized by all 

 strains and fructose by almost all. Paraffin 

 was utilized by all strains of A^. asteroidcs 

 and A^. hrasiliensis. Mariat recorded the fol- 

 lowing series for two species of nocardia and 

 three streptomyces : 



A'^. asteroidcs: Glucose > fructose > 

 glycerol > mannitol > the otlun- carbon 

 compounds which were praxrtically not uti- 

 lized. 



N. hrasiliensis: (Uycei-ol > glucose > 

 fructose > galactose > mannitol > xy- 

 lose > arabinose > saccharose > maltose > 

 the other compounds which were practically 

 not utilized. 



S. madurac: Glucose > glyccM'ol > 

 starch > xylose > mannitol > fructose > 

 saccharose > galactose > maltose > Na 



acetate > lactose > Xa citrate > the other 

 compounds which were not utilized. 



*S'. peUrtieri: Glucose > fructose > Na 

 acetate > the othei- compounds tested 

 which were not utilized. 



S. somaliensis: Glucose > maltose > 

 fructose > the other compounds tested 

 which were not utilized. 



As sources of energy and carbon, proteins 

 and their derivatives are freciuently pre- 

 fei'red to (carbohydrates by actinomy(;etes, 

 especially species of Streptomyces. This is 

 shown by the fact that when a protein or a 

 peptone is present in the same medium with 

 glucose or another available ctu'bohydrate, 

 an actinomycete may attack the protein 

 first, not only as a source of nitrogen but also 

 as a source of energy and carbon; consider- 

 able waste nitrogen is thereby liberated in 

 the form of ammonia. The favorable effect 

 of glucose in increasing the growth of actino- 

 mycetes in the presence of protein is due 

 partly to the neutralizing effect on the am- 

 monia produced from the peptone by the 

 acid foi'med from the glucose. Tyrosine can 

 be used by certain species of Strcptomijces, 

 with the formation of dark-pigmented com- 

 pounds. Some of the amino acids, like leucine, 

 are utilized by actinomycetes only in the 

 presence of an available carbohydrate ("I'ea 

 can serve as a source of nitrogXMi, but not of 

 carbon. 



The metabolic changes iinoh'ed in the 

 utilization of i)olypeptides and amino acids 

 as sources of carbon have been studied by 

 Woodruff and Foster (Table 2(5). 



Dtcom position of Cellulose, 

 ('liilin, and Agar 



Among the carbon sources for the nutri- 

 tion of actinomycetes, cellulose occupies a 

 uni(iue place. The (capacity of certain actino- 

 mycetes to de(H)mpose cellulose is well estab- 

 lislunl. The cellulose-plate method or a li(iuid 

 medium containing the necessary inorganic 

 salts, a source of nitrogen, and filter paper 



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