 |
Inhaltsübersicht | Nanomaschinen | Moleküle | Programme | Kurse | Fun | Links |
 |
| > |
The Glycolytic Enzymes
Phosphoglycerate Kinase
Now, at the seventh step of glycolysis, the cell is ready to make some ATP. The glucose has been split into two halves, each of which now has two phosphates attached. Phosphoglycerate kinase takes these molecules and transfers one of the phosphates to ADP, creating a new ATP molecule. As with the first enzyme of glycolysis, this process must be shielded from water to ensure that the phosphate gets transferred correctly. Phosphoglycerate kinase uses the same approach taken by hexokinase: it closes around the reaction, protecting it away from interfering water molecules. The enzyme is composed of two lobes connected by a flexible linker. The upper lobe binds to ADP and the lower one has a pocket for the glucose fragment. Then it hinges close and performs the transfer. The PDB entry 3pgk, shown on the left, is in the open form with ADP bound, and PDB entry 1vpe, on the right, shows a closed form.Last changed by: A.Honegger,