Holoenzyme can be defined as the active form of the enzyme. Holoenzyme is made of 2 components called the apoenzyme and coenzyme. If a cofactor is an organic molecule, then it is called as a coenzyme. The apoprotein can be defined as the inactive form of the holoenzyme, which requires binding of coenzyme. On binding with the cofactor, the apoenzyme gets activated which results in the formation of the functional holoenzyme.