Alcohols, Glycols and Compounds 

 Related to Sugars 



Two of the most important routes of sugar metabolism are 

 the Embden-Meyerhof pathway of anaerobic glycolysis and the 

 oxidative pentose phosphate cycles. Both occur widely in nature, 

 and microorganisms were useful in the discovery of each. Many 

 of the metabolites of this chapter can be pictured as arising 

 from one of these schemes, which are also the main known 

 routes of glucose metabolism in mammals. It should be under- 

 stood that other paths and fragments of paths of glucose metab- 

 olism have been found in various microorganisms. 



Yeast was instrumental in the elucidation of the Embden- 

 Meyerhof route^ and the yeast alcohol fermentation is repre- 

 sented as follows, each step catalyzed by a specific enzyme: 



Embden-Meyerhof Route of Anaerobic Glycolysis in Yeast 



Enzymes 



1. Hexokinase 



2. Phosphohexoisomerase 



3. Phosphohexokinase 



4. Aldolase 



5. Triosephosphate isomerase 



6. Triosephosphate dehydrogenase (Inhibited by iodoacetate) 



7. ATP-Phosphoglyceric transphosphorylase 



8. Phosphoglyceromutase 



9. Enolase (Inhibited by fluoride) 



10. ATP-Phosphopyruvic transphosphorylase 



11. Carboxylase 



12. Alcohol dehydrogenase 



^ A. J. Kluyver and C. B. Van Niel, "The Microbe's Contribution to 

 Biology," Harvard University Press, Cambridge, Massachusetts, 1956. 



