ubiquinone

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Related to ubiquinones: Coq10

coenzyme

 [ko-en´zīm]
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.

u·bi·qui·none

(ū'bi-kwī'nōn, ū-bik'wi-nōn),
A 2,3-dimethoxy-5-methyl-1,4-benzoquinone with a multiprenyl side chain; a mobile component of electron transport.
See also: coenzyme Q.

ubiquinone

(yo͞o′bĭ-kwĭ-nōn′, -kwĭn′ōn′)
n.
A quinone compound that serves as an electron carrier between flavoproteins and in cellular respiration.

coenzyme Q10

A factor present in mitochondria which extracts energy from foods. It has acquired a reputation among fringe nutritionists as being effective in detoxifying patients with an overdose of environmental pollutants; it is also claimed to be beneficial in treating hypertension, obesity, periodontal disease, preventing cancer, increasing longevity and revitalising the immune system.

u·bi·qui·none

(yū'bi-kwi'nōn)
A 2,3-dimethoxy-5-methyl-1,4-benzoquinone with a multiprenyl side chain; a mobile component of electron transport.
See also: coenzyme Q

ubiquinone

or

coenzyme Q

a type of QUINONE that can be reversibly reduced. It functions as an electron carrier in ELECTRON TRANSPORT SYSTEMS.
References in periodicals archive ?
Isoprenoid includes cholesterol, bile acids, steroid hormones, dolichol, ubiquinone, prenylated proteins, and a wide variety of plant terpenoids [1].
In P falciparum, the biosynthesis of ubiquinone or coenzyme Q involves two major steps: synthesis of the benzoquinone by the shikimate pathway and synthesis of the isoprene side chain by the MEP pathway.
Since antioxidants act not individually, but synergistically, a mixture of vitamin E, ubiquinone [Q.sub.9], and [beta]-carotene was added to the animal diet.
A diet enriched with [beta]-carotene (2 mg/kg body weight), [alpha]-tocopherol (2 mg/kg body weight), and ubiquinone [Q.sub.9] (8 mg/kg body weight) was administered daily for 15 days prior to LPS treatment.
The kinetics of the redox reactions of ubiquinone related to the electron-transport activity in the respiratory chain.
Branch-point reactions in the biosynthesis of cholesterol, dolichol, ubiquinone and prenylated proteins.
Whether this represents occupation of an inhibitory binding site similar to group II ubiquinones or interference in cyclophylin D binding to the pore is unknown.
Laaksonen, "Molecular dynamics simulations of ubiquinone; a survey over torsional potentials and hydrogen bonds," Molecular Physics, vol.
Coenzyme [Q.sub.10] (Co[Q.sub.10]), the predominant ubiquinone species in humans, functions as an electron carrier in the mitochondrial electron transport chain (ETC) and as an intracellular antioxidant (1).
Reference Baseline values values TBARS < 4.50 4.380 [+ or -] 0.153 [gamma]-Tocopherol 2.00-700 1.625 [+ or -] 0.160 [alpha]-Tocopherol 15-40 17.98 [+ or -] 0.920 [beta]-Carotene 0.30-3.00 0.983 [+ or -] 0.164 Co[Q.sub.10-TOTAL] 0.40-1.00 0.512 [+ or -] 0.164 Ubiquinol (3 months) TBARS 4.200 [+ or -] 0.241 [gamma]-Tocopherol 1.927 [+ or -] 0.304 [alpha]-Tocopherol 19.14 [+ or -] 0.872 [beta]-Carotene 0.804 [+ or -] 0.129 Co[Q.sub.10-TOTAL] 3.016 [+ or -] 0.307 * [micro]mol-L: micromol-liter; TBARS: thiobarbituric acids reactive substances; [gamma]-tocopherol: gamma-tocopherol; [alpha]-tocopherol: alpha-tocopherol; Co[Q.sub.10total] (ubiquinol + ubiquinone); data are expressed as mean [+ or -] standard error of the mean; * P < 0.0001.
Plasma ubiquinone to ubiquinol ratio in patients with hepatitis, cirrhosis, and hepatoma, and in patients treated with percutaneous transluminal coronary repertusion.
Previous reports of the activity of complex I have varied according to the enzyme preparations and the ubiquinone species used.