Citric acid cycle definition

How did the citric acid cycle come into being Although definitive answers are elusive, it is nevertheless instructive to speculate how this complicated central hub of metabolism developed. We can perhaps begin to comprehend how evolution might work at the level of biochemical pathways. 

As far as the 1953 selection of the Nobel Prize winners for science is concerned, one could look at this event as a perfect stage management of the Nobel Committee. The Nobel Prize for Medicine and Physiology went to Hans Krebs for the Citric acid cycle and enzymatic reactions , to Fritz Lipmann for Coenzyme A , and the Nobel Prize for Chemistry to Hermann Staudinger [7, p. 1064]. In addition, Watson and Crick had just rang in molecular biology definitely with their Nature article on their DNA model [18]. 

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