Electron Transport Chain

Electron Transport Chain

An electron transport chain (ETC) couples electron transfer between an electron donor (such as NADH) and an electron acceptor (such as O2) with the transfer of H+ ions (protons) across a membrane. The resulting electrochemical proton gradient is used to generate chemical energy in the form of adenosine triphosphate (ATP). Electron transport chains are the cellular mechanisms used for extracting energy from sunlight in photosynthesis and also from redox reactions, such as the oxidation of sugars (respiration).

In chloroplasts, light drives the conversion of water to oxygen and NADP+ to NADPH with transfer of H+ ions across chloroplast membranes. In mitochondria, it is the conversion of oxygen to water, NADH to NAD+ and succinate to fumarate that are required to generate the proton gradient. Electron transport chains are major sites of premature electron leakage to oxygen, generating superoxide and potentially resulting in increased oxidative stress.

Read more about Electron Transport Chain:  Background, Electron Transport Chains in Mitochondria, Electron Transport Chains in Bacteria, Photosynthetic Electron Transport Chains, Summary

Other articles related to "electron transport chain, electron, electrons, electron transport chains":

Alternative Oxidase - Function
... oxidase diverges from the cytochrome-linked electron transport chain at the ubiquinone pool ... reactive oxygen species and infection by pathogens, as well as other factors that reduce electron flow through the cytochrome pathway of respiration ... depends entirely on the alternative oxidase pathway for cellular respiration through its electron transport chain ...
Light-dependent Reactions - Photosynthetic Electron Transport Chains in Bacteria - Cyanobacteria
... chlorophylls, as antenna pigments), but their electron transport chain H2O → PS II → plastoquinone → b 6 → cytochrome c 6 → PS I → ferredoxin → NADPH ↑ ↓ b 6 ← plastoquinone is, in essence ... The mobile water-soluble electron carrier is cytochrome c 6 in cyanobacteria, plastocyanin in plants ... The electron transport chain is NADH dehydrogenase → plastoquinone → b 6 → cytochrome c 6 → cytochrome aa 3 → O2 where the mobile electron carriers are plastoquinone and cytochrome c 6, while the ...
Mitochondrion - Function - Energy Conversion - NADH and FADH2: The Electron Transport Chain
... transferred to oxygen (O2) in several steps via the electron transport chain ... system of antiporter proteins or feed into the electron transport chain using a glycerol phosphate shuttle ... This process is efficient, but a small percentage of electrons may prematurely reduce oxygen, forming reactive oxygen species such as superoxide ...
Mitochondrial Matrix - Electron Transport Chain
... The electron transport chain is located in the cristae of the inner mitochondrial membrane ... NADH and FADH2 produced by the citric acid cycle in the matrix release a proton and electron to regenerate NAD+ and FAD ... pulled into the intermembrane space by the energy of the electrons going through the electron transport chain ...
Electron Transport Chain - Summary
... Electron transport chains are redox reactions that transfer electrons from an electron donor to an electron acceptor ... The transfer of electrons is coupled to the translocation of protons across a membrane, producing a proton gradient ...

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