Mechanism of proton translocation associated to oxidation of N,N,N′,N′‐tetramethyl‐p‐phenylenediamine in rat liver mitochondria

FEBS Letters

Guerrieri, F.¹  Papa, S.¹  Boffoli, D.¹  Izzo, G.¹ 

[1] Institute of Biological Chemistry, Faculty of Medicine, University of Bari, Bari, Italy

关键词: Cytochrome oxidase;    Redox-linked proton translocation;    TMPD oxidation;    Cytochrome oxidation;    Hydrogenated donor;    oxidation of;    TMPD;    N;    N;    N′;    N′-tetramethyl-p-phenylenediamine;    TMPD+;    oxidised free radical form of TMPD (Wuster's blue);    FCCP;    p-trifluoromethoxy-carbonylcyanide;    UHDBT;    5-(n-undecyl)-6-hydroxyl-4;    7-dioxobenzothiazole;    NEM;    N-ethylmaleimide;    EGTA;    ethyleneglycol bis (β-aminoethyl ether)-N;    N′-tetra-acetate;    Hepes;    N-2-hydroxyethylpiperazine-N′-2-ethanesulphonate;   

DOI  :  10.1016/0014-5793(83)81107-7

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

A kinetic analysis is presented of proton translocation, TMPD⁺ formation and oxidation of endogenous respiratory carriers during oxygen pulses of TMPD supplemented rat-liver mitochondria. The results show that antimycin-insensitive proton ejection observed under coupled conditions derives from oxidation of endogenous respiratory carriers and re-reduction of TMPD⁺ by hydrogenated donors and not from proton pumping by cytochrome oxidase as claimed by other investigators. The observations presented provide an example of certain interpretative difficulties in the use of redox mediators and of the methodological approaches that can be used to avoid these.

【 授权许可】

Unknown