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Discussion 



conditions, despite the fact that some kind of steady state is finally 

 reached, which might be equal or different for both conditions. 



Lynen: I agree that if you study different conditions you will have 

 different effects. I would emphasize that the control of fermentation by 

 lack of ADP seems to me impossible if ATP is available at the same time. 

 The phosphorylation of hexose by ATP would continuously regenerate 

 ADP. 



Hess : This is a question of the ratio between dephosphorylation and 

 phosphorylation. In non-respiring ascites cells the ATP/ADP ratio is 

 1/1 and in respiring cells it is about 7/1 or even 10/1. 



Lynen : I do not agree on this point. According to our analysis, and 

 as far as I know, Prof. Holzer has had similar results, the ATP/ADP 

 ratio does not change when you switch from nitrogen to oxygen. How- 

 ever, these determinations did not differentiate between cytoplasmic 

 and mitochondrial ATP ; the eventual transport of ATP from cytoplasm 

 to mitochondria could not be detected by our method. 



4 



