In this video, we're going to introduce Phosphorylation. Phosphorylation refers to the transfer of a phosphate group from ATP to another molecule to provide energy. Phosphorylation by ATP hydrolysis can have a wide variety of effects, including activating a target molecule so that it's capable of reacting and changing the conformation of a target protein. Notice in the image below, we show a glucose molecule as a green hexagon, depicted as the inactive form of glucose, unable to react. However, after ATP hydrolysis and the phosphorylation of the glucose molecule, where phosphorylation is the transfer of a phosphate group from ATP to another molecule, this phosphorylated form of glucose becomes active and capable of reacting.
Notice that adenosine triphosphate, ATP, has three phosphates, whereas ADP only has two phosphates. The third phosphate was transferred over to glucose, as illustrated. This form of glucose is the active form and can proceed to react. Phosphorylation does not always lead to activation of a target molecule; this is just an example of what phosphorylation can achieve.
Remember, phosphorylation leads to a wide variety of effects. In some scenarios, it will lead to activation, but in other scenarios, it could lead to inactivation. The idea here is that phosphorylation can have a wide variety of effects. Over here on the right-hand side, we're focusing on a protein. This red circle represents a protein. Notice that after ATP hydrolysis and phosphorylation of the protein, the protein takes on a completely different conformation, changing its shape, structure, and likely its function as well. You can see the phosphorylated protein here has an altered conformation.
This concludes our introduction to phosphorylation and how ATP is usually the source of the phosphate group in phosphorylation. Phosphorylation can lead to a wide variety of effects, including activating a target to react and changing the conformation of a target protein.
So, this concludes our lesson, and I'll see you guys in our next video.