Reaction Mechanism and Applications of Glucose Isomerase

Glucose Isomerase (Product ID: 99064) is an enzyme that catalyzes the reversible isomerization of D-glucose to D-fructose.

Reaction Mechanism

The primary reaction is the conversion of an aldose (glucose) into a ketose (fructose):
D-glucose ⇌ D-fructose

The process generally involves the following steps:

1. Ring Opening: The enzyme facilitates the opening of the glucose sugar ring from its cyclic form to its linear chain form.
2. Isomerization: The enzyme catalyzes the shift of a hydrogen atom, transforming the aldehyde group at the C1 position of glucose into a ketone group at the C2 position, effectively turning it into fructose. This step typically requires metal ions (such as Magnesium or Manganese) as cofactors.
3. Ring Closure: The linear fructose molecule is then closed back into its cyclic form.

Industrial Applications

• Food Industry: It is most famously used to produce High-Fructose Corn Syrup (HFCS). Since fructose is sweeter than glucose, this process increases the sweetness of corn-derived syrups.
• Biofuels: It is used to convert glucose into fructose, which can be more efficiently fermented into ethanol.
• Biotechnology: Used in the synthesis of specialty sugars and other chemical derivatives.

This enzyme is highly valued in industrial processes because it can perform this conversion efficiently under relatively mild conditions (temperature and pH).