Table of standard reduction potentials for half-reactions important in biochemistry

The values below are standard reduction potentials for half-reactions measured at 25°C, 1 atmosphere and a pH of 7 in aqueous solution.[1][2]

Half-reaction Δξ°'(V) E' Physiological conditions References and notes
CH3COOH + 2 H+ + 2 eCH3CHO + H2O -0.58
2 H+ + 2 e → H2 -0.42
NAD+ + H+ + 2 e → NADH -0.320 -0.280 The ratio of NAD+:NADH is maintained at around 30:1.[3] This allows NAD+ to be used to oxidise organic molecules
NADP+ + H+ + 2 e → NADPH -0.320 -0.370 The ratio of NADP+:NADPH is maintained at around 1:50.[3] This allows NADPH to be used to reduce organic molecules
FAD + 2 H+ + 2 e → FADH2 (coenzyme bonded to flavoproteins) -0.22 Depending on the protein involved, the potential of the flavine can vary widely[4]
O2 + 2 H+ + 2 eH2O2 +0.30
O2 + 4 H+ + 4 e → 2 H2O +0.82
P680+ + e → P680 ~ +1.0

Notes

    References

    1. Berg JM, Tymoczko JL, Stryer L, (2001) Biochemistry, 5th edition, WH Freeman, New York
    2. Voet D, Voet JG, Pratt CW, (2013) Fundamentals of Biochemistry, 4th edition, John Wiley & Sons, New York
    3. 1 2 Huang, Haiyan; Shuning Wang; Johanna Moll; Rudolf K. Thauer (2012-07-15). "Electron Bifurcation Involved in the Energy Metabolism of the Acetogenic Bacterium Moorella thermoacetica Growing on Glucose or H2 plus CO2". Journal of Bacteriology. 194 (14): 3689–3699. doi:10.1128/JB.00385-12. ISSN 0021-9193. Retrieved 2013-09-10.
    4. Buckel, W.; Thauer, R. K. (2013). "Energy conservation via electron bifurcating ferredoxin reduction and proton/Na+ translocating ferredoxin oxidation". Biochimica et Biophysica Acta (BBA) - Bioenergetics. 1827 (2): 94. doi:10.1016/j.bbabio.2012.07.002.


    This article is issued from Wikipedia - version of the 7/20/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.