Intermediate Carbohydrate 

 Metabolism 



OTTO MEYERHOF 



University of Pennsylvania 



THIS REVIEW OF THE intermediary carbohydrate metabolism must 

 necessarily be treated broadly and generally, for the subject 

 has many diflFerent aspects, and the detailed questions of hydro- 

 gen transport, Pasteur eflFect, pyridine nucleotides, cocarboxylase, 

 metabolic cycles, phosphorylations, indeed all the items which are 

 intrinsic elements of the present picture of carbohydrate breakdown, 

 will be dealt with by competent investigators of these subjects. 

 Moreover, I had the opportunity to discuss the special question of 

 oxidoreduction and dismutation in carbohydrate metabolism at the 

 Chicago congress some months ago. 



If we take this occasion to look back fifty years and to compare 

 our present knowledge with that which existed at the end of the 

 last century we have reason to be very proud, for at that time this 

 whole field appeared nearly as tabula rasa. But two outstanding 

 achievements had already been accomplished: first, Claude Ber- 

 nard's work on the interconversion of glucose and glycogen in the 

 liver and on the role of blood sugar under normal and diabetic 

 conditions; second, the work of Pasteur on the different microbic 

 fermentations as manifestations of the anaerobic metabolism of 

 these organisms. Nothing was known about the oxidative break- 

 down of sugar. Although lactic acid formation in the blood and 

 especially in the muscles had been observed by Claude Bernard 

 and others, it was not known whether nor how this cleavage was 

 connected with respiration. 



Since then the interconversion of glycogen and blood sugar have 

 continued to claim the attention of medical investigators, and re- 

 cently, as you know, a highly interesting development was reported: 

 Professor Cori's discovery of glucose-1-monophosphoric acid as inter- 

 mediary. The old problem of diabetes was shifted by the isolation 

 of insulin from the study of blood sugar regulation to the bio- 

 chemical task of studying tissue metabolism under the influence of 

 added hormones. The third old problem of the connection between 



