Review Note

Why is the isomerization of glucose-6-phosphate (G6P) to fructose-6-phosphate (F6P) crucial for the progression and efficiency of glycolysis?

a. The isomerization of G6P to F6P is an irreversible reaction, which commits the intermediates downstream of the glycolytic pathway.

b. The isomerization shifts the equilibrium of glycolysis toward ATP production by facilitating the direct transfer of phosphate groups to ADP.

c. The conversion from an aldose to a ketose sugar is necessary because only fructose-6-phosphate can be cleaved into two symmetrical 3-carbon intermediates after phosphorylation by PFK-1, ensuring the generation of triose phosphates.

d. Isomerizing G6P to F6P increases the affinity of hexokinase for glucose, ensuring that the rate of glucose entry into glycolysis is optimized in response to cellular energy needs.