Sandbox Reserved 401: Difference between revisions
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Hexokinase is transferase protein. It is the first enzyme in the glycolytic pathway that converts glucose into glucose-6-phosphate. This enzyme uses ATP to phophorylate the 6-hydroxyl group of glucose, which is inhibited by its product, glucose-6-phosphate. It is also allosterically relieved of product ihibition by the addition of phosphate.Hexokinase controls the flow of glucose into energy metabolism in many mammalian tissues, such as blood cells, and the brain. Glucose-6-phoshate and glucose bind synergeticly to hexokinase, as well as glucose and phosphate. This posphate however plays a small role in the regulation of hexokinase during respiration. This is because gylcolysis is limited by the supply og glucose. | Hexokinase is transferase protein. It is the first enzyme in the glycolytic pathway that converts glucose into glucose-6-phosphate. This enzyme uses ATP to phophorylate the 6-hydroxyl group of glucose, which is inhibited by its product, glucose-6-phosphate. It is also allosterically relieved of product ihibition by the addition of phosphate.Hexokinase controls the flow of glucose into energy metabolism in many mammalian tissues, such as blood cells, and the brain. Glucose-6-phoshate and glucose bind synergeticly to hexokinase, as well as glucose and phosphate. This posphate however plays a small role in the regulation of hexokinase during respiration. This is because gylcolysis is limited by the supply og glucose. | ||
== Reaction == | |||
During the first step of glycolysis, the gama-phosphoryl group af n ATP molecule is trasferred to the oxygen at the C-6 position of glucose. A magnesium ion is required as the reactive form of ATP is the chelated complex with magneium (II) ion. This is a direct nucleophillic attack of the hydroxyl group on the terminal phosphoryl group of ATP molecule. This reaction produces glucoe-6-phosphate, and ADP. | |||