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The protein component of an enzyme, excluding additional components such as cofactors or inhibitors.


(Biochemistry) a protein component that together with a coenzyme forms an enzyme


(ˌæp oʊˈɛn zaɪm)

the protein component that with a coenzyme forms a complete enzyme.
[1935–40; < French]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.apoenzyme - a protein that combines with a coenzyme to form an active enzyme
protein - any of a large group of nitrogenous organic compounds that are essential constituents of living cells; consist of polymers of amino acids; essential in the diet of animals for growth and for repair of tissues; can be obtained from meat and eggs and milk and legumes; "a diet high in protein"
References in periodicals archive ?
In the case of PNPO deficiency, plasma AADC activity can be increased, probably owing to upregulation of apoenzyme synthesis in the absence of the PLP cofactor.