METABOLISM OF ACTINOMYCETES 



25 



the production of ammonia, the bacterium, which is recognized 

 as not very active proteolytically (B. coli), and the actino- 

 mycetes were repressed in their action upon the proteins to a 

 much smaller extent. 



It is quite possible that here as well as in the case of higher 

 animals we have two kinds of metabolism: endogenous and ex- 

 ogenous. A definite quantity of ammonia may always be pro- 

 duced out of protein materials, as a waste product, independent 

 of whether an available carbohydrate is present or absent; this 



TABLE 7 



The action of microorganisms on peptone in presence and absence of available 

 carbohydrates.* Period of incubation seven days at 37° 



ORGANISMS 



Control 



B. coli 



B. proteus 



Aspergillus niger 



Act. diastaticus 



Act. viridochromogenus 



Act. fradii 



Act. griseus 



Act. poolensis 



BOUILLON 



NHi-N 



45.73 

 50.44 

 73.75 

 33.93 

 89.09 

 68.74 

 63.43 

 97.35 

 80.83 



NHs-N 





 9.45 

 32.55 

 32.60 

 11.55 

 10.50 



13.65 

 12.60 



BOUILLON PLUS 1 PER 

 CENT GLUCOSE 



NH2-N 



44.25 

 47.79 

 48.08 

 21.54 

 67.85 

 50.15 

 56.64 

 85.24 

 67.85 



nh 3 -n 





 7.35 

 8.40 



15.80 

 9.45 



10.50 



11.55 



12.60 



The data present milligrams of nitrogen per 100 cc. of medium. 



ammonia may be reabsorbed, in the presence of available car- 

 bohydrates, by organisms that are able to utilize it readily as a 

 source of nitrogen (A. niger). In the absence of available carbo- 

 hydrates, the strongly proteolytic organisms use the proteins 

 readily as sources of carbon, leaving large quantities of ammonia, 

 as waste material, in the medium. The ammonia produced 

 in the first case, will not be appreciably decreased (except when 

 reutilized again), while the production of ammonia in the second 

 case may be entirely prevented by a utilizable carbohydrate. 



The milk data in table 5 point clearly to the fact that most of 

 the actinomycetes can attack the milk proteins readily and split 

 them to amino acids and ammonia. This question was dis- 



