Reversible inhibition of electron transfer in the ubiquinol

[摘要]

Electron transfer through the ubiquinol:cytochrome c ₁-segment of liver mitochondria isolated from hibernating ground squirrels Citellus undulatus is repressed by 70–80% as compared to mitochondria from the active animals. The inhibition site is likely to be localized between ubiquinone and the cytochrome bc ₁, complex. Partial release of the inhibition can be observed upon swelling of the isolated mitochondria in a hypoosmotie medium, the effect being prevented by phospholipase A₂ inhibitors. Possible role of phospholipase A₂ in regulation of ubiquinol oxidation by complex bc ₁, is discussed.

[学科分类] 生物化学/生物物理

[关键词] Oxidative phosphorylation;Electron flow regulation;Hibernation;Phospholipase A2;Ubiquinol: cytochrome c 1 reductase;Citellus undulatus;TMPD N;N;N';N'-tetramethyl-p-phenylenedi-amine;BrPhBr;bromphenacylbromide