PHOSPHATE TURNOVER AND PASTEUR EFFECT 



F. Lynen, G. Hartmann, K. F. Netter and 



A. SCHUEGRAF 

 Max-Planck-Institut fur Zellchemie, Munich 



In 1941, Lynen and Johnson developed independently a 

 theory of the Pasteur effect. This effect is the inhibition of 

 fermentation by respiration, and could be explained in terms 

 of appropriation of intracellular inorganic phosphate by the 

 respiratory system. The theory was based on Harden and 

 Young's (1905) fundamental discovery that sugar fermenta- 

 tion depends on the presence of free phosphate. Later, 

 Warburg and Christian (1939) found the chemical explana- 

 tion for this phenomenon when they studied the mode of 

 action of crystalline triose phosphate dehydrogenase. They 

 performed kinetic measurements of the dehydrogenation 

 reaction, which is the keystone of energy production in 

 fermentation, and found that it requires inorganic phosphate, 

 the concentration of which can thus control the reaction 

 rate. Following the discovery that respiration, also, is depen- 

 dent on inorganic phosphate (Engelhardt, 1932; Kalckar, 

 1937; Belitzer, 1939), the ground was prepared for our 

 theory of the Pasteur effect : under aerobic conditions respira- 

 tion competes with fermentation for the inorganic phosphate 

 in the cell. 



This metaboUc regulation of the living cell is controlled by 

 the "phosphate cycle". By this term the compensation of 

 adenosine triphosphate (ATP) synthesis by the cleavage 

 reactions yielding inorganic phosphate may be described. The 

 ATP synthesized in exergonic catabohsm is used for the 

 great variety of energy-requiring reactions connected with the 

 process of life. The two parts of the cycle, phosphorylation 

 and dephosphorylation, have to be equilibrated against each 



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