CHAPTER 4 



The Chemistry of Photosynthesis 



A. INTRODUCTORY NOTES 



§ 44 Essentials of Glycolysis 



Originally Lepine (19) called glycolysis the breakdown of hexoses in the 

 tissues. Later, Warburg (34) restricted this term to the anaerobic break- 

 down to the stage of lactic acid. It has long been known that inorganic phos- 

 phate is indispensable to carbohydrate breakdown. During glycolysis, phos- 

 phorylations take place giving rise to the formation of hexose phosphates and 

 triose phosphates. 



The first step of glycolysis concerns the conversion of Cg-molecules char- 

 acterized by the following reactions 



hexokinase 



glucose > glucose-6-phosphate 



A TP Mg ions 



phosphohexo- 

 glucose-6-phosphate ^ ^ fructose-6-phosphate 



isomerase 



phosphofrnctokinase 

 fructose-6-phosphate ^ * fructose-l,6-diphosphate 



A TP Mg ions 



The second step deals with the formation of Cs-molecules. It begins with 

 the splitting of fructose-l,6-diphosphate into 3-phosphoglyceraldehyde and 

 phosphodihydroxyacetone 



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