340 



AUGUSTO BONAZZI 



Calculating the C02:02 ratio we obtain the value 1.07. Here 

 again a very close approach is seen to the value obtained by 

 Krzmieniewsky when glucose was used as a source of carbon. 

 Again here as in the previous experiment the carbon dioxid 

 dissolved in solution was determined and found to be 44.36 

 mgm. and the quantity of this gas in the atmosphere 1037.0 

 mgm. The total weight of the gas formed then would be 1081.4 

 mgm. while a total quantity of 703.3 mgm. of oxygen was con- 

 sumed. A determination of the sugar concerned in the action 

 follows: 



Uninoculated 1701 . mgm. CeHnOe 



Inoculated 572.8 mgm. CeHnOe 



Total sugar consumed 1128.2 mgm. 



If we assmne that the consumed oxygen was utihzed wholly in 

 the process of sugar combustion we obtain the balances shown 

 in table 5. 



TABLE 5 

 Gas balances in cultures of Azotobacter 



Here again we see indications of an intramolecular respiration 

 taking place with a consumption of sugar above the theoretical.^ 



Comparing now the data from the two experiments mentioned 

 above we have table 6. 



It seems evident therefore that the cells of Azotobacter besides 

 retaining abundant stores of the carbohydrate with which they 



' A third experiment of the series, in which the C02:02 ratio has been deter- 

 mined, gave a value of 1.09 for the respiratory exchange, a value in very close 

 agreement to the others here reported. A summary of the C02:02 ratios follows: 



Experiment 44 1 . 08 



Experiment 46 1 . 07 



Experiment 78 1.09 



Value of Krzmieniewsky 1 .02 



