Final answer:
Glucose-6-phosphate undergoes isomerization to become fructose-6-phosphate, catalyzed by the enzyme phosphogluco-isomerase in the second step of glycolysis. This reaction sets the stage for the molecule's eventual split into two three-carbon molecules.
Step-by-step explanation:
The enzymatic process involving the conversion of glucose-6-phosphate to fructose-6-phosphate is known as isomerization. This reaction is catalyzed by the enzyme phosphogluco-isomerase, and it is the second step in the metabolic pathway of glycolysis. Isomerization is essential because it allows the six-carbon ring structure of glucose-6-phosphate to rearrange itself into fructose-6-phosphate, a key step that facilitates the eventual split of the sugar molecule into two three-carbon molecules later in the glycolytic pathway. The transition from glucose-6-phosphate to fructose-6-phosphate is essential as it prepares the molecule for subsequent phosphorylation and cleavage into three-carbon units. After this conversion, the enzyme phosphofructokinase-1 adds another phosphate group to produce fructose-1,6-bisphosphate, eventually leading to the generation of two molecules of glyceraldehyde-3-phosphate.