coenzyme Q

Also found in: Dictionary, Thesaurus, Acronyms, Encyclopedia, Wikipedia.


an organic molecule, usually containing phosphorus and some vitamins, sometimes separable from the enzyme protein; a coenzyme and an apoenzyme must unite in order to function (as a holoenzyme).
coenzyme A a coenzyme essential for carbohydrate and fat metabolism; among its constituents are pantothenic acid and a terminal SH group, which forms linkages with various acids, e.g., acetic acid (acetyl CoA) and fatty acids (acyl CoA); abbreviated CoA.
coenzyme Q any of a group of related quinones occurring in the lipid fraction of mitochondria and serving, along with the cytochromes, as an intermediate in electron transport; they are similar in structure and function to vitamin K1.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

co·en·zyme Q (CoQ, Q),

Designation applied to ubiquinones with isoprenoid side chains consisting of variable numbers of isoprene units. CoQ mediates electron transfer between cytochromes b and c, and is chemically similar to vitamins E and K and to other tocopherols, quinones, and tocols. the length of the isoprenoid side chain distinguishes one type of CoQ from another; for example, ubiquinone-10, the typical mammalian ubiquinone, has a side-chain of 10 isoprene units.
Farlex Partner Medical Dictionary © Farlex 2012

coenzyme Q

The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.

co·en·zyme Q

Quinones with isoprenoid side chains (specifically, ubiquinones) that mediate electron transfer between cytochrome b and cytochrome c.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012

coenzyme Q (ubiquinone)

a quinone derivative with a variable length isoprenoid side chain at position 6 on the molecule. Ubiquinone is an oxidation-reduction COENZYME that functions in the respiratory ELECTRON TRANSPORT SYSTEM as a carrier of electrons between DEHYDROGENASES and CYTOCHROMES.
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005
References in periodicals archive ?
Turunen M, Olsson J, Dallner G, 2004, Metabolism and function of coenzyme Q. Biochimica Biophysica Acta.
Biosynthesis of the isoprenoid quinones menaquinone (vitamin K2) and ubiquinone (coenzyme Q).