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The protein component of an enzyme, excluding additional components such as cofactors or inhibitors.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Biochemistry) a protein component that together with a coenzyme forms an enzyme
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˌæp oʊˈɛn zaɪm)

the protein component that with a coenzyme forms a complete enzyme.
[1935–40; < French]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
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"
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
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.