496 



AUGUSTO BONAZZI 



dependent upon its carbon nutrition. The free carbon 

 dioxide is not only necessary for growth but is also necessary 

 for the performance of the normal oxidative functions peculiar to 

 the cells. Therefore nitrosofermentation which is supposed 

 to furnish the energy for the carbon assimilation can not even 

 be established in the absence of free carbon dioxide. The 

 small quantity of nitrite formation in the presence of KOH, if 

 positive at all, must be considered as the result of an autooxi- 

 dation of the cells themselves and a utilization of the energy 

 thus liberated, for the process of nitrite formation, a process 

 which soon comes to a standstill because of the strong negative 

 pressure of the CO2 outside the cell and of the subsequent 

 diffusion of the intracellular material towards the outside, and 

 also because of the strong alkalinity developed in the medium. 



(nitrification) (respiratioq) 



-««8»0 



'z 





Fig. 3 



This interpretation leads to a special conception of the life of 

 the organisms of nitrosofermentation. When the optimum car- 

 bon dioxide tension is existent, the cells, during their life cycle, 

 perform two synchronous functions; one of cellular respira- 

 tion and one of carbon assimilation, the former serving for the 

 initiation of the process of nitrosofermentation and subsequent 



