What type of reaction occurs in Step 9 of glycolysis?

In Step 9 of glycolysis, which involves the conversion of 2-phosphoglycerate (2-PG) to phosphoenolpyruvate (PEP) via the action of the enzyme enolase, a dehydration reaction takes place. This reaction specifically entails the removal of a water molecule from 2-PG, leading to the formation of a double bond in PEP.

Dehydration reactions, also known as condensation reactions, occur when two molecules combine with the loss of a water molecule. In this case, the conversion of 2-PG to PEP effectively results in the formation of a more energetically favorable compound while releasing water as a byproduct. The resulting PEP is a high-energy substrate used in the subsequent step of glycolysis for ATP production.

Understanding this step is crucial as it highlights the importance of dehydration reactions in the metabolic pathway, contributing to the overall energy yield during glycolysis.