Glucose-6-Phosphatase

Glucose -6-phosphatase (abbr.: G6Pase, Gene: G6PC ) is the name of the enzyme that catalyzes the cleavage of phosphate from glucose 6 -phosphate ( G6P ). This reaction is an indispensable part of step several energy metabolic pathways in vertebrates. In humans three isoforms of the enzyme are produced, which are G6PC, G6PC2 G6PC3 and encoded by the genes; the corresponding enzymes called G6Pase, G6Pase -2 and G6Pase - third G6Pase is to be found in humans in the liver, the kidneys and in small amounts in the intestine G6Pase -2 is specifically localized in islet cells, the enzyme activity of G6Pase -3 is doubtful. Mutations in G6PC are responsible for by - Gierke disease type Ia, and variations in G6PC2 are associated with high glucose levels during fasting ( FGQTL1, > 5.55 mmol / l glucose ), a risk factor for diabetes mellitus; Lack of G6PC -3 can eventually lead to severe familial neutropenia type 4 ( SCN4 ).

The G6Pasen are membrane proteins in the endoplasmic reticulum (ER), which, together with glucose -6-phosphate translocase a protein complex. This complex simultaneously ensures the inflow of G6P to the interior (lumen) of the ER, and for the hydrolysis of G6P to glucose and phosphate. Finally, the glucose is transported from the ER, the exact mechanism is still unknown (2008).

Catalyzed reaction

H2O Pi

G6P is hydrolyzed to glucose. The reaction is practically irreversible.

The reaction is sub-step of gluconeogenesis.

Protein isoform Euteleostomi Glycogen storage disease type I SLC37A4
269535
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