Compare the delta ΔG0' values for the oxidation of succinate by NAD+ and by FAD. Use the data given in Table 18.1 to find the E0' of the NAD+-NADH and fumarate-succinate couples, and assume that E0' for the FAD – FADH2 redox couple is nearly 0.05 V. Why is FAD rather than NAD+ the electron acceptor in the reaction catalyzed by succinate dehydrogenase? TABLE 18.1 Standard reduction potentials of some reactionsOxidantReductantE, (V)Succinate + CO,a-KetoglutarateAcetaldehydeFerredoxin (reduced)H,NADH + H+2-0.67Acetate2-0.60Ferredoxin (oxidized)1-0.432 H+2-0.42NAD+2-0.32NADP+ΝADPH + H ,2-0.32Lipoate (oxidized)Glutathione (oxidized)Lipoate (reduced)Glutathione (reduced)2-0.292-0.23FADFADH,2-0.22AcetaldehydeEthanol2-0.20PyruvateLactate-0.192 H*H,2-0.00!FumarateSuccinate2+0.03Cytochrome b (+3)DehydroascorbateCytochrome b (+2)1+0.07Ascorbate2+0.08Ubiquinone (oxidized)Cytochrome c (+3)Fe (+3)½02 + 2 H*Ubiquinone (reduced)Cytochrome c (+2)Fe (+2)2+0.101+0.221+0.77H,O2+0.822.

∆G' 0= -nFE'0where n = number of electrons transferredF = Faraday's constant∆G' 0 = Standard Gibb's…

Compare the delta ΔG0' values for the oxidation of succinate by NAD+ and by FAD. Use the data given in Table 18.1 to find the E0' of the NAD+-NADH and fumarate-succinate couples, and assume that E0' for the FAD – FADH2 redox couple is nearly 0.05 V. Why is FAD rather than NAD+ the electron acceptor in the reaction catalyzed by succinate dehydrogenase?

Compare the delta ΔG0' values for the oxidation of succinate by NAD+ and by FAD. Use the data given in Table 18.1 to find the E0' of the NAD+-NADH and fumarate-succinate couples, and assume that E0' for the FAD – FADH2 redox couple is nearly 0.05 V. Why is FAD rather than NAD+ the electron acceptor in the reaction catalyzed by succinate dehydrogenase?

Biochemistry

6th Edition

ISBN:9781305577206

Author:Reginald H. Garrett, Charles M. Grisham

Publisher:Reginald H. Garrett, Charles M. Grisham

Chapter18: Glycolysis

Section: Chapter Questions

Problem 16P: Energetics of the Hexokinase Reaction The standard-state free energy change. Gfor the hexokinase...

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