Term: cofactors
https://doi.org/10.1351/goldbook.C01128

Definition:
Organic molecules (cf. coenzymes) or ions (usually metal ions) that are required by an enzyme of its activity. They may be attached either loosely or tightly prosthetic group) to the enzyme. A cofactor binds with its associated protein (apoenzymes), which is functionally inactive, to form the active enzyme (holoenzyme).

Related Terms:
1) coenzymes (http://doi.org/10.1351/goldbook.C01126).
2) enzyme (http://doi.org/10.1351/goldbook.E02159).
3) prosthetic group (http://doi.org/10.1351/goldbook.P04893).
4) holoenzyme (http://doi.org/10.1351/goldbook.H02836).

Source: PAC, 1992, 64, 143. 'Glossary for chemists of terms used in biotechnology (IUPAC Recommendations 1992)' on page 150 (https://doi.org/10.1351/pac199264010143)

Citation: 'cofactors' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.C01128

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