Glucose: Its Role in Energy & Cellular Function

Glucose is one of the most critical carbohydrates needed by our bodies. The breakdown of this simple sugar gives living cells the energy they require to survive.

Features

• Glucose is a six-carbon molecule with multiple hydroxyl groups attached. Its most common form is a ringed pyranose structure, shown in the image. It can also be found in a five-ringed furanose form or a linear string of carbons, but these are not favorable structures.

Function

• Glucose is mainly used by the body for short-term energy. Glucose is taken up by cells and converted to pyruvate in a multistep, multienzyme process called glycolysis. Glucose residues are also linked to serine and threonine amino acids of glycoproteins.

Types

• Besides the forms found in solution, glucose can have two configurations. D-glucose is the form which can be utilized by the human body. Its mirror image configuration, L-glucose, cannot be recognized by our enzymes.

Significance

• Hyperglycemia, or too much glucose in the blood, and hypoglycemia, or too little glucose in the blood, are hallmark characteristics of diabetes.

Fun Fact

• The amount of glucose stored in our bodies would allow us to survive for about a day. It is our fat stores that allow for longer starvation.