Effects of bc 1‐site electron transfer inhibitors on the absorption spectra of mitochondrial cytochromes b

FEBS Letters

Surkov, Sergey¹  Kunz, Wolfram S.²  Kamensky, Yuriy²  Konstantinov, Alexander A.² 

[1] Institute of Biological Testing of Chemical Compounds, Moscow Region, Kupavna, ul. Kirova 23, USSR;A.N. Belozersky Laboratory of Molecular Biology and Bioorganic Chemistry, Moscow State University, Moscow 119899 USSR

关键词: Cytochrome b;    Q cycle;    Spectral shift;    Respiratory chain;    Electron transfer inhibitor;    NoHOQnO;    2-nonyl-4-hydroxyquino-line-N-oxide;    SMP;    submitochondrial particles;   

DOI  :  10.1016/0014-5793(85)81120-0

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Changes are described that are brought about by antimycin, NoHOQnO, funiculosin, myxothiazol and mucidin in the α-, β- and γ-absorption bands of reduced and oxidized cytochromes b in the isolated complex bc ₁, form beef heart mitochondria. The inhibitors can be divided into 2 groups. Antimycin, funiculosin and NoHOQnO are likely to shift the spectrum of b-562 and compete for specific binding with complex bc ₁ with each other but not with myxothiazol and mucidin. The spectral effects of the latter two inhibitors are more difficult to interpret and may involve contributions not only from b-562 but from b-566 as well. The existence of 2 independent inhibitor binding-sites in the complex bc ₁ corroborates the Q-cycle hypothesis.

【 授权许可】

Unknown