Prosthetic group

Prosthetic Group

A prosthetic group is a non-protein molecule required for the activity of a protein. Prosthetic groups are organic or inorganic, non-peptide molecules bound to a protein that facilitate its function. Prosthetic groups include cofactors, which are bound tightly to proteins and are necessary for their function, but are not proteins themselves.

Function

Prosthetic groups are essential for the biological activity of certain proteins. They can be organic molecules such as vitamins or lipids, or inorganic molecules such as metal ions. Prosthetic groups can be permanently bound to the protein (for example, in hemoglobin) or they can be loosely and reversibly bound.

Examples

Some examples of proteins with prosthetic groups include hemoglobin, cytochrome c, and catalase. In these proteins, the prosthetic group is an integral part of the protein's structure that enables it to carry out its function.

See also

• Holoenzyme
• Apoenzyme
• Coenzyme
• Cofactor (biochemistry)