Explain different types of cofactors.

Cofactors : Non protein constituents of enzyme are called cofactors.
* Cofactors are of 3 types namely prosthetic group, coenzymes and metal ions.
* Prosthetic group - Organic cofactors tightly bound to the apoenzyme.

 Eg: Haem of peroxidase and catalase.
* Coenzymes-Organic cofactors loosely bound to the apoenzyme.
Eg : NAD and NADP contain the vitamin niacin.
* Metal ions-Inorganic cofactor forms coordination bonds with side chains at the active site and substrate

 Eg : Zinc for carboxypeptidase.