Plasma membrane NADH‐coenzyme Q0 reductase generates semiquinone radicals and recycles vitamin E homologue in a superoxide‐dependent reaction

FEBS Letters

Navas, Placido²  Villalba, Jose M²  Arroyo, Antonio¹  Tyurin, Vladimir A¹  Tyurina, Yulia Y¹  Kagan, Valerian E¹ 

[1] Department of Environmental and Occupational Health, University of Pittsburgh, 260 Kappa drive, Pittsburgh, PA 15238, USA;Departamento de Biologia Celular, Universidad de Cordoba, Cordoba, Spain

关键词: NADH-coenzyme Q0 reductase;    Semiquinone radical;    Vitamin E recycling;    Superoxide;    Coenzyme Q0;    Trolox;    PMQR;    plasma membrane NADH-CoQ reductase;    CoQ0;    2;    3-dimethoxy-5-methyl-1;    4 benzoquinone;    ubiquinone Q0;    CoQ0H2;    ubiquinol Q0;    DFO;    deferoxamine mesylate;    DOPC;    l-alpha-phosphatidylcholine;    dioleoyl (C18:1;    [cis]-9) synthetic;    SOD;    superoxide dismutase;    EPR;    electron paramagnetic resonance;    DMPO;    5;    5-dimethyl-1-pyrroline N-oxide;    CHAPS;    (3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate);   

DOI  :  10.1016/S0014-5793(98)00482-7

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

We investigated the ability of plasma membrane CoQ reductase (PMQR) purified from pig liver to reduce phenoxyl radicals of a vitamin E homologue, Trolox. We report that NADH-driven one-electron reduction of CoQ₀ catalyzed by PMQR produced CoQ₀ semiquinone radical and CoQ₀H₂. These in turn, recycle vitamin E homologue, Trolox, via reducing its phenoxyl radical. A significant part of NADH/PMQR-catalyzed reduction of CoQ₀ (and Trolox recycling) was superoxide-dependent. Overall, our results demonstrate that PMQR in the model system used can act as an antioxidant enzyme that recycles water-soluble homologues of coenzyme Q and vitamin E.

【 授权许可】

Unknown