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10.3: Electron transport chain- complexes and reactions catalyzed

\(\mathrm{Donor\: (red) + Acceptor\: (ox) \Rightarrow Donor\: (ox) + Acceptor\: (red)}\)

\[\mathrm{\Delta \epsilon ^{\circ’}=\epsilon ^{\circ’}\: Acceptor - \epsilon ^{\circ’}\: donor}\]

\[\mathrm{Same\: as\: \Delta \epsilon ^{\circ’}=\epsilon^{\circ’}\: Acceptor+ (-\epsilon ^{\circ’})\: donor}\]

Complex I

\[\mathrm{NADH+H^{+}+CoQox \Rightarrow NAD^{+}+ CoQred\: (CoQH_{2})}\]

\[\mathrm{\Delta \epsilon^{\circ’}=\underline{\:\:\:\:\:}\:\:\:\:\: \Delta G^{\circ’}=\underline{\:\:\:\:\:}}\]

Complex II

\[\mathrm{succinate+ CoQox \Rightarrow Fumarate + CoQred}\]

\[\mathrm{\Delta \epsilon^{\circ’}=\underline{\:\:\:\:\:}\:\:\:\:\: \Delta G^{\circ’}=\underline{\:\:\:\:\:}}\]

Complex III

\[\mathrm{CoQred + 2Cyt.\: c_{ox} \Rightarrow CoQox+ 2Cyt.\: c_{red} + 2H^{+}}\]

\[\mathrm{\Delta \epsilon^{\circ’}=\underline{\:\:\:\:\:}\:\:\:\:\: \Delta G^{\circ’}=\underline{\:\:\:\:\:}}\]

Complex IV- different balanced reactions

\[\mathrm{1Cyt.\: c_{red}+1H^{+} + 1/4O_{2} \Rightarrow 1Cyt.\: c_{ox} + 1/2H_{2}O}\]

\[\mathrm{2Cyt.\: c_{red}+2H^{+} + 1/2O_{2} \Rightarrow 2Cyt.\: c_{ox} + 1H_{2}O}\]

\[\mathrm{4Cyt.\: c_{red}+4H^{+} + 1O_{2} \Rightarrow 4Cyt.\: c_{ox} + 2H_{2}O}\]

\[\mathrm{\Delta \epsilon^{\circ’}=\underline{\:\:\:\:\:}\:\:\:\:\: \Delta G^{\circ’}=\underline{\:\:\:\:\:}\: Not\: the\: same,\: for\: all\: reactions,\: depend\: on\: number\: of\: electrons}\]