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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 ?
It has a flavin adenine dinucleotide (FAD) redox point, which is entirely surrounded in the apoenzyme. It acts upon by catalysis transfer of the electron from glucose to gluconolactone.
However, it is impossible to calibrate procedures for aminotransferases that do not incorporate P-5'-P using a procedure that does, such as the reference measurement procedure (RMP), because the ratio of preformed holoenzyme to apoenzyme differs among specimens (5).
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.
KMO exists as an apoenzyme and interacting with flavin-adenine dinucleotide (FAD) forms a holoenzyme; the flavin moiety of the protein acts as an electron donor [27].
Isolation of the holo- and apoenzymes and conversion of the apoenzyme to the holoenzyme," Journal of Biological Chemistry, vol.