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How do cofactors and coenzymes help enzymes catalyze reactions?

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nanoparticles: hydrogen peroxide — catalysis Nanoparticles of a gold-palladium (yellow-blue) alloy supported on acid-treated carbon (gray) directly catalyzing hydrogen peroxide formation from hydrogen (white) and oxygen (red) while shutting off unwanted hydrogen peroxide decomposition.

Cofactors are essential nonprotein components required for the biological activity of an enzyme. Without these components, the protein portion of the enzyme, known as the apoenzyme, lacks catalytic activity.1

Cofactors assist in chemical reactions through several key mechanisms:
* Direct Participation: They often participate directly in reactions by facilitating the transfer of electrons, atoms, or functional groups between molecules.1
* Substrate Binding: They help ensure that substrates are properly attached to the enzyme’s active site.1
* Structural Support: Some cofactors provide necessary structural support to maintain the three-dimensional shape of the enzyme.1

Coenzymes are a specific type of cofactor that bind loosely to the enzyme. Unlike prosthetic groups, they are freely diffusing organic compounds that participate in catalysis in stoichiometric amounts. During a reaction, coenzymes are modified and may require a subsequent enzyme-catalyzed process to be restored to their original state. Many B vitamins function as coenzymes, playing vital roles in metabolic processes.12