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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 ?
The apoenzyme activity was quantified as the difference between total and holoenzyme activities.
Purification of recombinant Helicobacter pylori urease apoenzyme encoded by ureA and ureB.
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.