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10.3: Electron transport chain- complexes and reactions catalyzed

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    6066
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    \(\mathrm{Donor\: (red) + Acceptor\: (ox) \Rightarrow Donor\: (ox) + Acceptor\: (red)}\)

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

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

    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

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

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

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

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