Interpretation :
standard Gibbs free energy and Gibbs free energy for the gluconeogenesis in the erythrocytes should be calculated.
Introduction :
In gluconeogenesis glucose is produced from the non-carbohydrate substances. This is an anabolic reaction and can be considered as the reverse of the catabolic reactions. For this question, generation of glucose from pyruvate is considered. This reaction sequence can be considered as the reverse of the glycolysis that occurs with the help of set of anabolic enzymes and energy carrier molecules.
Explanation of Solution
All the reactions in glycolysis are reversed in the gluconeogenesis. However, energy of the reactions that occur with hexokinase, phosphofructokinase, and pyruvate kinase enzymes changes depending on the ATP, ADP, Pi, GTP and GDP concentrations. Therefore, ΔG values changes. For other reactions, ΔG values can be obtained by reversing the sign of the respective values indicated in 18.1 table as they are the reverse reactions.
ΔGfor conversion of Pyruvateto PEP
ΔGofor the conversion of PEP to pyruvate is
That is the ΔGofor the reverse reaction.
ΔGfor conversion of Fructose-1,6-bisphosphate to fructose-6-phosphate
F6P = fructose-6-phosphate
F1,6BP = Fructose-1,6-bisphosphate
ΔGfor conversion of glucose-6-phosphate to glucose
G6P = glucose-6-phosphate
Therefore, with the other values final ΔG for the entire process,
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Chapter 22 Solutions
Biochemistry
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