How to Convert Glycogen to Glucose

Animals usually store long-term energy as fats. However, fats take a while before the body can retrieve that energy, so it is important for animals to store some readily available energy as well. This energy is stored in the form of glycogen in the livers and muscles of most animals. Glycogen is a branched polysaccharide made up solely of linked glucose molecules, and those glucose molecules must be released to retrieve the energy.

Things You'll Need

• Glycogen
• Purified water
• Phosphorylase
• Phosphoglucomutase
• Glucose-6-phosphatease
• Benedict's quantitative solution

Instructions

1. Suspend the glycogen in purified water. Add phosphorylase to the glycogen. This process will create glucose-1-phosphate molecules that have broken off of the main glycogen molecule.

2. Add phosphoglucomutase to the reaction. This will further prepare the glucose for metabolism and create the glucose-6-phosphate molecule.

3. Add the glucose-6-phosphatease. This will remove the phosphate, leaving a phosphate molecule and a regular glucose molecule that can be absorbed and used by cells.

4. Test the solution periodically in a side test tube for presence of glucose with Benedict's quantitative solution. The different colors that show up will represent successively greater concentrations of glucose if the reaction is proceeding.

Tips & Warnings

• These enzymes are just catalysts that should not be used up during the reaction, so you can use them sparingly. If the Benedict's is not showing strong glucose concentrations, add more enzymes.

• Your body uses glucagon and/or epinephrine to activate many of these enzymes, so they may be required to simulate this in situ.

References

• National Instititue of Health Books: Glycogen Metabolism
• Central Washington University: Glycogen Metabolism
• Glycogen Metabolism