PAP2_like proteins, glucose-6-phosphatase subfamily. Glucose-6-phosphatase converts glucose-6-phosphate into free glucose and is active in the lumen of the endoplasmic reticulum, where it is bound to the membrane. The generation of free glucose is an important control point in metabolism, and stands at the end of gluconeogenesis and the release of glucose from glycogen. Deficiency of glucose-6-phosphatase leads to von Gierke's disease.