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Escherichia coli K-12 substr. MG1655 Reactions Class: Electron-Transfer-Reactions

Summary:
Electron transfer reactions (ETRs) describe reactions that transfer electrons between substrates, which are thus involved in redox processes that oxidize and reduce some of the substrates. ETRs usually take place at membranes, because a key purpose of ETRs is to use the electron energy to build up a proton gradient across the membrane, which can then be used for energy generation by the cell, using ATP synthesis driven by the proton gradient. ETRs very often involve the pool of membrane-bound quinone substrates, which can shuttle electrons to or from an ETR.

All ETRs are composite reactions, because they involve at least two redox half reactions. These half reactions involve explicit electrons, which cannot occur freely. Thus, the half reactions have to be paired up, with the result that the electrons are used only internally to connect the half reactions, and are not visible as substrates of the ETR.

Sometimes, a proton transport reaction can also be a sub-reaction of the ETR, to represent so-called vectoral proton movement. In the vectoral case, protons are actively pumped across the membrane, using energy extracted from the redox processes. The proton transport reaction is not directly connected to the redox half reactions in the pathway representation of the composite reaction.

Because ETRs tend to occur at membranes, substrates that are not in the default compartment (the cytoplasm) need to have compartment information associated by means of value annotations. The exception to this are the membrane-bound quinone substrates, which are always assumed to reside in the membrane itself.

Parent Classes:
Composite Reactions

Instances:
1.1.5.2: β-D-glucose[periplasmic space] + an ubiquinone[inner membrane] → D-glucono-1,5-lactone[periplasmic space] + an ubiquinol[inner membrane] ,
1.1.5.2: D-glucopyranose[periplasmic space] + an ubiquinone[inner membrane] → D-glucono-1,5-lactone[periplasmic space] + an ubiquinol[inner membrane] ,
1.1.5.3: sn-glycerol 3-phosphate + an ubiquinone[inner membrane] → glycerone phosphate + an ubiquinol[inner membrane] ,
1.1.5.3: sn-glycerol 3-phosphate + a menaquinone[inner membrane] → glycerone phosphate + a menaquinol[inner membrane] ,
1.1.5.4: (S)-malate + an electron-transfer quinone[inner membrane] → oxaloacetate + an electron-transfer quinol[inner membrane] ,
1.1.5.6: formate[periplasmic space] + a menaquinone[inner membrane] + 2 H+ → CO2[periplasmic space] + a menaquinol[inner membrane] + H+[periplasmic space] ,
1.1.5.-: (R)-lactate + an ubiquinone[inner membrane] → pyruvate + an ubiquinol[inner membrane] ,
1.2.5.1: pyruvate + an ubiquinone[inner membrane] + H2O → CO2 + acetate + an ubiquinol[inner membrane] ,
1.3.5.1: succinate + an ubiquinone[inner membrane] → fumarate + an ubiquinol[inner membrane] ,
1.3.5.2: (S)-dihydroorotate + an electron-transfer quinone[inner membrane] → orotate + an electron-transfer quinol[inner membrane] ,
1.3.5.2: (S)-dihydroorotate + a menaquinone[inner membrane] → orotate + a menaquinol[inner membrane] ,
1.3.5.2: (S)-dihydroorotate + an ubiquinone[inner membrane] → orotate + an ubiquinol[inner membrane] ,
1.3.5.3: protoporphyrin IX + 3 a menaquinol[inner membrane] ← protoporphyrinogen IX + 3 a menaquinone[inner membrane] ,
1.3.5.4: fumarate + a menaquinol[inner membrane] ↔ succinate + a menaquinone[inner membrane] ,
1.4.5.1: a D-amino acid + an electron-transfer quinone[inner membrane] + H2O → ammonium + a 2-oxo carboxylate + an electron-transfer quinol[inner membrane] ,
1.4.5.-: D-alanine + an electron-transfer quinone[inner membrane] + H2O → ammonium + pyruvate + an electron-transfer quinol[inner membrane] ,
1.5.5.2: L-proline + an ubiquinone[inner membrane] → (S)-1-pyrroline-5-carboxylate + an ubiquinol[inner membrane] + H+ ,
1.6.5.2: an electron-transfer quinone[inner membrane] + NAD(P)H + H+ → an electron-transfer quinol[inner membrane] + NAD(P)+ ,
1.6.5.3: NADH + an ubiquinone[inner membrane] + 5 H+ ↔ NAD+ + an ubiquinol[inner membrane] + 4 H+[periplasmic space] ,
1.6.5.9: NADH + an ubiquinone[inner membrane] + H+ → NAD+ + an ubiquinol[inner membrane] ,
1.6.5.10: NADPH + an electron-transfer quinone[inner membrane] + H+ → NADP+ + an electron-transfer quinol[inner membrane] ,
1.6.5.-: NADH + a menaquinone[inner membrane] + 5 H+ → NAD+ + a menaquinol[inner membrane] + 4 H+[periplasmic space] ,
1.7.2.3: trimethylamine N-oxide[periplasmic space] + a menaquinol[inner membrane] + H+[periplasmic space] → trimethylamine[periplasmic space] + a menaquinone[inner membrane] + H2O[periplasmic space] ,
1.7.5.1: nitrate + a menaquinol[inner membrane] + 2 H+ → nitrite + a menaquinone[inner membrane] + H2O + 2 H+[periplasmic space] ,
1.7.5.1: nitrate + an ubiquinol[inner membrane] + 2 H+ → nitrite + an ubiquinone[inner membrane] + 2 H+[periplasmic space] + H2O ,
1.7.99.4: nitrate[periplasmic space] + an ubiquinol[inner membrane] → nitrite[periplasmic space] + an ubiquinone[inner membrane] + H2O[periplasmic space] ,
1.8.5.3: dimethyl sulfide[periplasmic space] + a menaquinone[inner membrane] + H2O[periplasmic space] ← dimethyl sulfoxide[periplasmic space] + a menaquinol[inner membrane] ,
1.10.3.10: 2 an ubiquinol[inner membrane] + oxygen + 8 H+ → 2 an ubiquinone[inner membrane] + 2 H2O + 8 H+[periplasmic space] ,
1.10.3.14: 2 an ubiquinol[inner membrane] + oxygen + 4 H+ → 2 an ubiquinone[inner membrane] + 2 H2O + 4 H+[periplasmic space] ,
1.12.99.6: a menaquinone[inner membrane] + 2 H+ + H2[periplasmic space] → a menaquinol[inner membrane] + 2 H+[periplasmic space] ,
NADH + a menaquinone[inner membrane] + H+ → NAD+ + a menaquinol[inner membrane]


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Please cite the following article in publications resulting from the use of EcoCyc: Nucleic Acids Research 41:D605-12 2013
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