Glucose-6-phosphatase

Glucose 6-phosphatase is an enzyme in the glycogenolysis pathway that removes the phosphate from glucose 6-phosphate. Also is the last step in gluconeogenesis (where the goal is to increase free glucose in the blood due to the body being in the catabolic state).

The main purpose of glucose 6-phosphatase is to dephosphorylate glucose 6-phosphate so that the free glucose can be exported from the cell via glucose transporter membrane proteins.

Locations
Glucose 6-phosphatase is found in the liver and kidney and is involved in the organs' role in glucose homeostasis. Glucose-6-phosphatase is located on the inner membrane of the endoplasmic reticulum of the liver and kidney. Muscle and brain do not contain glucose 6-phosphatase; as a result any glucose 6-phosphate produced by glycogenolysis is used to generate ATP via glycolysis.

According to Surholt and Newsholme, glucose 6-phosphatase activity IS present in a wide variety of muscles across the animal kingdom.

Clinical Significance
A deficiency in glucose 6-phosphatase can lead to a glycogen storage disease called von Gierke's disease.