However, some enzymes also require a non-protein component called a cofactor. Cofactors can be:

* Metal ions: Like zinc, iron, magnesium, or copper.

* Organic molecules: Like vitamins or coenzymes.

These cofactors help the enzyme function properly, often by:

* Providing a binding site for the substrate.

* Participating in the chemical reaction.

Therefore, while enzymes are primarily proteins, their full functionality may depend on the presence of additional cofactors.