1、呼吸链（电子传递链) 真核生物的呼吸链 原核生物的呼吸链
真核生物的呼吸链 原核生物的呼吸链 1、呼吸链(电子传递链)
4H' 4H 2H' Intermembrane Space FeS.-Cytc- 28 Cyt as FMN FeS NADH NAD FAD +H中 4H 4H' 202+2HH0 -2H Succinate Fumarate Matrix
真核生物呼吸链的蛋白质组成 Protein Components of the Mitochondrial Electron-Transfer Chain Mass Number of Prosthetic Enzyme complex (kDa) subunits* group(s) I NADH 850 42(14) FMN,Fe-S dehydrogenase lI Succinate 140 5 FAD,Fe-S dehydrogenase IlI Ubiquinone: 250 11 Hemes,Fe-S cytochrome c oxidoreductase Cytochrome ct 13 1 Heme IV Cytochrome 160 13(3-4) Hemes;CuA,CuB oxidase *Numbers of subunits in the bacterial equivalents in parentheses. Cytochrome c is not part of an enzyme complex;it moves between Complexes Ill and IV as a freely soluble protein
真核生物呼吸链的蛋白质组成
CHs CHsO. (CH2-CH-C-CH2)1o-H Ubiquinone (Q) (fully oxidized) CH3O 辅酶Q CH3 H' +e 0 CHO R Semiquinone radical (QH) CHO CH3 OH H*+e OH CH2O R Ubiquinol (QH2) (fully reduced) CHsO CH3 OH
辅酶 Q
Standard Reduction Potentials of Respiratory Chain and Related Electron Carriers Redox reaction(half-reaction) E'(V) 2H+2e→H2 -0.414 NAD+H+2E→NADH -0.320 NADP++H+2E→NADPH -0.324 NADH dehydrogenase (FMN)+2H'+2e-NADH dehydrogenase(FMNH2) -0.30 Ubiquinone 2H*+2e ubiquinol 0.045 Cytochrome b(Fe)+ecytochrome b(Fe2) 0.077 Cytochrome c(Fe3)+ecytochrome c (Fe2+) 0.22 Cytochrome c(Fe3)+ecytochrome c(Fe2) 0.254 Cytochrome a(Fe3)+ecytochrome a(Fe2*) 0.29 Cytochrome a (Fe3)+ecytochrome aa (Fe2") 0.55 202+2H+2e→H,0 0.816