STUDIES IN THE METABOLISM OF ACTINOMYCETES 

 III. NITROGEN METABOLISM 



SELMAN A. WAKSMAN 

 Department of Soil Bacteriology, New Jersey Agricultural Experiment Station 



Received for publication, July 11, 1919 



The utilization of different nitrogenous compounds by actino- 

 mycetes and the transformation of these substances due to the 

 action of the organisms will be taken up in the present paper. 



Rullman (1899) stated that Actinomyces odorifer cannot nitrify. 

 Beijerinck (1900) observed the reduction of nitrates to nitrites 

 by actinomycetes. Nadson (1903) found that organisms of this 

 type from mineral mud are able to decompose proteins very 

 readily with the liberation of ammonia and hydrogen sulfide. 

 Mace (1905) noted that Cladothrix chromogena can split blood 

 serum, with the production of ammonia, propeptone and tyrosin 

 crystals. Fousek (1912) found that the actinomycetes isolated 

 from the soil assimilate nitrate, ammonia and amino-nitrogen 

 and reduce nitrates to nitrites, but cannot assimilate atmos- 

 pheric nitrogen. Miinter (1912) studied seven actinomycetes 

 isolated from the soil; scant growth or no growth at all was 

 obtained on nitrogen free media; all organisms were able to 

 utilize equally well nitrogen in the form of nitrates, ammonia 

 and asparagin; hemialbumin, casein, asparagin and alanin were 

 utilized readily and tyrosin to a smaller extent, both as sources 

 of carbon and nitrogen; urea, thiourea and dicyanamide gave 

 no growth at all when used as a source of both carbon and 

 nitrogen, but were used by some organisms as sources of nitro- 

 gen. Miinter (1914) has further shown that casein is ammon- 

 ified well, glue and peptone to a smaller extent, and urea only 

 very slightly; ammonia formed a good source of nitrogen, only 

 small quantities of nitrates being produced from this substance and 



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THE JOURNAL OF BACTERIOLOGY, VOL. V, NO. 1 



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