Phosphorylation is a quimical process which consists of the addition of a phosphate (PO4) group to a protein or other organic molecule such as glucose. Phosphorylation also involves the addition of phosphate to glucose to produce glucose monophosphate. Phosphorylation activates or deactivates many protein enzymes, causing or preventing the mechanisms of diseases such as cancer and diabetes.
Protein phosphorylation in particular plays a significant role in a wide range of cellular processes. Its prominent role in biochemistry is the subject of a very large body of research. Phosphorylation is carried out through the action of enzymes known as phosphotransferases or kinases.