coenzyme (cofactor)

A coenzyme (cofactor) is a non-protein chemical compound that is bound to a protein and is required for the protein\'s biological activity. These proteins are commonly enzymes, and cofactors can be considered \"helper molecules\" that assist in biochemical transformations.

Cofactors are either organic or inorganic. An inactive enzyme, without the cofactor is called an apoenzyme, while the complete enzyme with cofactor is the holoenzyme. Some enzymes or enzyme complexes require several cofactors. Organic cofactors are often vitamins or are made from vitamins.

Known coenzymes:

• nikotineamideadeninedinukleotide (NAD)
• nikotineamideadeninedinukleotidfosfate (NADP)
• flavinemononukleotide (FMN)
• flavineadenindinuleotide (FAD)
• coenzyme A
• coenzyme Q
• pyridexalphosfate (PLP)
• thiamindephosfate (TDP)