glycogen 



PRIMING REACTIONS 

 glucose 



227 



-56-7 



lactate 



-49-7/ 

 / 



2 lactates *^ 



\-62-2 



- 45-8 I - 45-8 

 alanine > pyruvate 



CO, 



ethanol 



I acetate 



i - 46-5 / 



acetaldehyde / +7-4 



- 55-0 I / 



I _ 48 ^ >/ + 6-S 

 acetylcoA 



+ oxaloacetate 

 - 7-8 



citrate 

 I +2-04 



cis-aconitate 

 1 -0-45 



isocitrate 

 I -47-0 



oxalosuccinate 

 I - 8-6 



- 45-9 i 



glutamate >■ a-ketoglutarate + COg 



I - 69-8 



succinate + COg 

 I - 35-7 



I 

 fumarate 

 I - 0-88 



malate 

 I - 44-8 



- 44-7 j 

 aspartate >■ oxaloacetate 



2 ethanols + CO, 



1 /2 butyrate 



i -43 

 1 /2 acetoacetate 



Fig. 57 (Krebs) — Changes in free energy (^Fo) in kcal. per mole at 25°, pH 7-2, 0-2 atm. 

 0,, 005 atm. COj. and the other reactants having a concentration of OOIM. The free 

 energy changes include changes due to associated reactions notably reactions with 

 molecular oxygen acting as an acceptor for hydrogen removed at various stages. 



Consequently, in the overall reaction for the oxidation of glucose, the moles 

 of ATP formed from ADP add up as follows : 



glucose —*2 pyruvate -{- 2 HoO 8 



2 pyruvate + 2 oxaloacetate + Oj -^ 2 citrate + 2 CO2 6 



2 citrate + 4 O2 -* 2 oxaloacetate + 4 HjO + 4 CO2 24 



Total 38 



The overall reaction can thus be written 



CeHiaOe + 6O2 + 38ADP + 38P -> 6H2O + 6CO2 + 38ATP 

 If glycogen is the starting point, we may add 1 ATP, giving a total of 

 39 ATP. 



