Assay conditions for the mitochondrial NADH:coenzyme Q oxidoreductase

FEBS Letters

Estornell, Ernesto¹  Lenaz, Giorgio¹  Pallotti, Francesco¹  Fato, Romana¹ 

[1] Dipartimento di Biochimica, Università di Bologna, Via Irnerio 48, 40126-Bologna, Italy

关键词: NADH:CoQ oxidoreductase;    Coenzyme Q homolog and analog;    Beef heart mitochondria;    CoQn;    ubiquinone or coenzyme Q (n = 0–10 refer to the number of isoprenoid units in the lateral chain);    DQ;    duroquinone;    DB;    6-decylubiquinone;    PB;    6-pentylubiquinone;    BHM;    beef heart mitochondria;    SMP;    submitochondrial particles;    NADH;    nicotinamide adenine dinucleotide;    reduced form;    PL;    phospholipid vesicles. Enzyme: NADH: coenzyme Q oxidoreductase EC 1.6.99.3 (Complex I);   

DOI  :  10.1016/0014-5793(93)80498-J

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The assay of Complex I activity requires the use of artificial acceptors, such as short-chain coenzyme Q homologs and analogs, because the physiological quinones, such as CoQ₁₀, are too insoluble in water to be added as substrates to the assay media. The medical interest raised in the last years on the pathological changes of Complex I activity has focussed on the requirement of easy reliable assays for its analysis. We have undertaken a systematic examination of the assay conditions of Complex I in mitochondrial membranes, using a series of quinones as electron acceptors, particularly the coenzyme Q homologs CoQ₀, CoQ₁ and CoQ₂, and the analogs duroquinone and decylubiquinone. Our findings have pointed out that the most suitable electron acceptor for the NADH:CoQ reductase assay is the homolog CoQ₁. The analog DB, commercially available, although yielding a high activity, nevertheless causes some problems for the standardization of the assay conditions.

【 授权许可】

Unknown