Term: apoenzyme
https://doi.org/10.1351/goldbook.A00417

Definition:
The protein part of an enzyme without the cofactor necessary for catalysis. The cofactor can be a metal ion, an organic molecule (coenzyme), or a combination of both.

Related Terms:
1) catalysis (http://doi.org/10.1351/goldbook.C00874).
2) coenzyme (http://doi.org/10.1351/goldbook.C01126).

Source: PAC, 1994, 66, 2587. 'Glossary of bioanalytical nomenclature - Part 1: General terminology, body fluids, enzymology, immunology (IUPAC Recommendations 1994)' on page 2593 (https://doi.org/10.1351/pac199466122587)

Citation: 'apoenzyme' 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.A00417

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