Abstract
The driving force, for all life as we know it, is derived from reduction–oxidation (redox) reactions. Most biological oxidations are often coupled to cellular energy production. Typically carbon compounds (such as carbohydrates) are oxidized to carbon dioxide, while oxygen is reduced to water. Enzymes play a significant role in connecting the series of redox reactions ultimately involving oxygen. In mitochondrial electron transport chain, electrons are passed from NADH along a series of electron acceptors/donors (oxidants and reductants) to O2. Molecular oxygen is the final oxidant (terminal electron acceptor) of aerobic metabolism. Biological reductions, on the other hand, are employed to store energy in chemical forms for later use. In photosynthetic organisms, reduction of carbon dioxide (to carbohydrates) is powered by sunlight, while water is oxidized (to oxygen). This broad canvas of redox reactions serves to drive pumps, maintain concentration gradients across membranes, and generate metabolites that have high group transfer potential and/or are energy rich. Not surprisingly, oxidoreductases form a significant group (EC 1.x.x.x) of well-represented enzymes (Chap. 4).
Life is interposed between two energy levels of the electron.
Albert Szent Gyorgyi
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References
Benkovic SJ (1980) On the mechanism of action of folate- and biopterin-requiring enzymes. Annu Rev Biochem 49:227–252
Duine JA (1999) The PQQ Story. J Biosci Bioengg 88:231–236
Fraaije MW, Mattevi A (2000) Flavoenzymes: diverse catalysts with recurrent features. Trends Biochem Sci 25:126–132
Joosten V, van Berkel WJH (2007) Flavoenzymes. Curr Opin Chem Biol 11:195–202
Klinman JP (1996) New quinocofactors in eukaryotes. J Biol Chem 271:27189–27192
Malmstrom BG (1982) Enzymology of oxygen. Annu Rev Biochem 51:21–59
Mattevi A (2006) To be or not to be an oxidase: Challenging the oxygen reactivity of flavoenzymes. Trends Biochem Sci 31:276–228
Matthews RG, Drummond JT (1990) Providing one-carbon units for biological methylations: mechanistic studies on serine hydroxymethyltransferase, methylene tetrahydrofolate reductase, and methyltetrahydrofolate-homocysteine methyltrasferase. Chem Rev 90:1275–1290
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Punekar, N.S. (2018). Enzymatic Oxidation–Reduction Reactions. In: ENZYMES: Catalysis, Kinetics and Mechanisms. Springer, Singapore. https://doi.org/10.1007/978-981-13-0785-0_33
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DOI: https://doi.org/10.1007/978-981-13-0785-0_33
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