ENDOGENOUS CAT ABOLISH 21 



withheld. This is the only carbon compound from which 

 this organism can build its cells. 



Aerobic and facultative bacteria, suspended in buffer 

 solution after washing, will take up from 7 to 35 mg. of 

 oxygen per gram bacteria solids per hour for two, and 

 even for ten hours at a constant rate. 



Streptococcus and Clostridium took up less than 

 0.5 c.c. during the first hour, and practically none later. 



SUMMARY OF THEORIES 



The loss of nitrogenous matter by starving cells is 

 supposed to be a normal process of all living cells which 

 is not ordinarily conspicuous because the opposite proc- 

 esses, growth and reconstruction, are more prominent. 



The nitrogenous products of endogenous catabolism 

 are the cleavage products of some thermolabile com- 

 pounds in the cell, such as enzymes, and living proto- 

 plasm. These compounds deteriorate at a definite rate 

 inside the cell as well as outside. 



The cell has the power to replace these compounds 

 from new food. In the absence of food, or in the 

 absence of appropriate food, the cell has ultimately not 

 enough of these essential molecules left, and dies. 



In the case of Nitromonas, the lack of non-nitrogenous 

 food caused the same symptom because with this 

 bacterium, all the carbon in any of the cell constituents 

 must come from carbon dioxide. 



