Oxidoreductase

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In biochemistry, an oxidoreductase is an enzyme that catalyzes the transfer of electrons from one molecule, the reductant, also called the electron donor, to another, the oxidant, also called the electron acceptor. This group of enzymes usually utilizes NADP+ or NAD+ as cofactors. [1] [2] Transmembrane oxidoreductases create electron transport chains in bacteria, chloroplasts and mitochondria, including respiratory complexes I, II and III. Some others can associate with biological membranes as peripheral membrane proteins or be anchored to the membranes through a single transmembrane helix. [3]

Contents

Reactions

For example, an enzyme that catalyzed this reaction would be an oxidoreductase:

A– + B → A + B–

In this example, A is the reductant (electron donor) and B is the oxidant (electron acceptor).

In biochemical reactions, the redox reactions are sometimes more difficult to see, such as this reaction from glycolysis:

Pi + glyceraldehyde-3-phosphate + NAD+ → NADH + H+ + 1,3-bisphosphoglycerate

In this reaction, NAD+ is the oxidant (electron acceptor), and glyceraldehyde-3-phosphate is the reductant (electron donor).

Nomenclature

Proper names of oxidoreductases are formed as "donor:acceptor oxidoreductase"; however, other names are much more common.[ citation needed ]

Classification

Oxidoreductases are classified as EC 1 in the EC number classification of enzymes. Oxidoreductases can be further classified into 21 subclasses:

See also

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In enzymology, a sorbitol-6-phosphate dehydrogenase (EC 1.1.1.140) is an enzyme that catalyzes the chemical reaction

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<span class="mw-page-title-main">D-xylulose reductase</span>

In enzymology, a D-xylulose reductase (EC 1.1.1.9) is an enzyme that is classified as an Oxidoreductase (EC 1) specifically acting on the CH-OH group of donors (EC 1.1.1) that uses NAD+ or NADP+ as an acceptor (EC 1.1.1.9). This enzyme participates in pentose and glucuronate interconversions; a set of metabolic pathways that involve converting pentose sugars and glucuronate into other compounds.

In enzymology, a 4-oxoproline reductase (EC 1.1.1.104) is an enzyme that catalyzes the chemical reaction

In enzymology, a mannitol-1-phosphate 5-dehydrogenase (EC 1.1.1.17) is an enzyme that catalyzes the chemical reaction

In enzymology, a mannuronate reductase (EC 1.1.1.131) is an enzyme that catalyzes the chemical reaction

<span class="mw-page-title-main">3-hydroxyacyl-CoA dehydrogenase</span> Enzyme

In enzymology, a 3-hydroxyacyl-CoA dehydrogenase (EC 1.1.1.35) is an enzyme that catalyzes the chemical reaction

In enzymology, a dihydrouracil dehydrogenase (NAD+) (EC 1.3.1.1) is an enzyme that catalyzes the chemical reaction

In enzymology, an enoyl-[acyl-carrier-protein] reductase (NADPH, A-specific) (EC 1.3.1.39) is an enzyme that catalyzes the chemical reaction

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<span class="mw-page-title-main">Glyceraldehyde-3-phosphate dehydrogenase (phosphorylating)</span>

In enzymology, a glyceraldehyde-3-phosphate dehydrogenase (phosphorylating) (EC 1.2.1.12) is an enzyme that catalyzes the chemical reaction

<span class="mw-page-title-main">NAD(P)H dehydrogenase (quinone)</span>

In enzymology, a NAD(P)H dehydrogenase (quinone) (EC 1.6.5.2) is an enzyme that catalyzes the chemical reaction

<span class="mw-page-title-main">Pyrroline-5-carboxylate reductase</span>

In enzymology, a pyrroline-5-carboxylate reductase (EC 1.5.1.2) is an enzyme that catalyzes the chemical reaction

<span class="mw-page-title-main">NADH:ubiquinone reductase (non-electrogenic)</span> Class of enzymes

NADH:ubiquinone reductase (non-electrogenic) (EC 1.6.5.9, NDH-2, ubiquinone reductase, coenzyme Q reductase, dihydronicotinamide adenine dinucleotide-coenzyme Q reductase, DPNH-coenzyme Q reductase, DPNH-ubiquinone reductase, NADH-coenzyme Q oxidoreductase, NADH-coenzyme Q reductase, NADH-CoQ oxidoreductase, NADH-CoQ reductase) is an enzyme with systematic name NADH:ubiquinone oxidoreductase. This enzyme catalyses the following chemical reaction:

References

  1. ↑ Eric J. Toone (2006). Advances in Enzymology and Related Areas of Molecular Biology, Protein Evolution (Volume 75 ed.). Wiley-Interscience. ISBN   0471205036.
  2. ↑ Nicholas C. Price; Lewis Stevens (1999). Fundamentals of Enzymology: The Cell and Molecular Biology of Catalytic Proteins (Third ed.). USA: Oxford University Press. ISBN   019850229X.
  3. ↑ Superfamilies of single-pass transmembrane oxidoreductases in Membranome database
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