KLUYVER S CONTRIBUTIONS TO MICROBIOLOGY AND BIOCHEMISTRY 



the dislocating influence of the protoplasm the triose would be rapidly 

 converted into carbon dioxide and alcohol ; the triose phosphate would 

 first have to be de-esterified before it, too, could yield the final fer- 

 mentation products. 



By further postulating that the rate of hydrolysis of the triose phos- 

 phate by yeast juice is smaller than the rate of formation of hexose 

 monophosphate, of its decomposition to triose and triose phosphate, 

 and of the triose breakdown, a result was obtained that was in full 

 agreement with experimental observations. In the first place it ex- 

 plained why the sugar decomposition was inextricably linked with the 

 formation of phosphate esters; the latter served in effect to prepare the 

 sugar molecule for its eventual breakdown. Secondly, the rapid for- 

 mation of triose phosphate and triose from the hexose monophosphate, 

 and the equally rapid disappearance of the triose, served to account 

 for the fact that, as Harden and Young had established, per molecule 

 of esterified phosphate one molecule of carbon dioxide and ethanol 

 each were generated. Thirdly, the low rate of hydrolysis of the triose 

 phosphate would cause this product to accumulate, so that gradually 

 an increasing amount of inorganic phosphate would become tied up; 

 following its complete disappearance the rate of production of carbon 

 dioxide and ethanol must needs become dependent on phosphate lib- 

 eration and the simultaneous triose formation by the dephosphoryla- 

 tion reaction. Fourthly, the accumulation of triose phosphate, accord- 

 ing to the proposed mechanism of its formation possessing the struc- 

 ture of 2-phosphoglyceraldehyde, would result in its condensation to 

 hexose diphosphate in a manner completely analogous to that of the 

 condensation of acetaldehyde to acetyl methyl carbinol which is ob- 

 served under conditions of aldehyde accumulation. And finally, the 

 hexose diphosphate so formed should be a keto-derivative, and the 

 identical one regardless of whether the fermentable sugar were glucose, 

 fructose, or mannose. That this was so had been established by Har- 

 den and co-workers. 



Without performing a single experiment, the available information 

 had thus been used to develop an hypothesis that, for the first time, 

 had accomplished an interpretation in which the formation of phos- 

 phate esters had been incorporated as a logical and indispensable ele- 

 ment in the picture of alcoholic fermentation. It stands to reason that 

 the same mechanism was proposed to explain the initial stages of sugar 



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