Enzyme Cofactor

An enzyme cofactor is a non-protein chemical compound or metallic ion that is required for an enzyme's catalytic activity. These molecules are essential "helper" components that enable or enhance the function of enzymes, which act as biological catalysts in various biochemical reactions. Cofactors can be inorganic ions (e.g., magnesium, zinc, iron, copper) or organic molecules (coenzymes, often vitamin-derived, like NAD+, FAD, heme, ATP). They facilitate the transfer of atoms, electrons, or functional groups; alter the enzyme’s active site; or participate directly in catalysis. Deficiencies can lead to severe metabolic disorders. Many cofactors must be obtained through diet.