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  2. Oxygen evolution - Wikipedia

    en.wikipedia.org/wiki/Oxygen_evolution

    Oxygen evolution is the chemical process of generating elemental diatomic oxygen (O 2) by a chemical reaction, usually from water, the most abundant oxide compound in the universe. Oxygen evolution on Earth is effected by biotic oxygenic photosynthesis , photodissociation , hydroelectrolysis , and thermal decomposition of various oxides and ...

  3. Photosystem II - Wikipedia

    en.wikipedia.org/wiki/Photosystem_II

    The experimental evidence that oxygen is released through cyclic reaction of oxygen evolving complex (OEC) within one PSII was provided by Pierre Joliot et al. [18] They have shown that, if dark-adapted photosynthetic material (higher plants, algae, and cyanobacteria) is exposed to a series of single turnover flashes, oxygen evolution is ...

  4. Oxygen-evolving complex - Wikipedia

    en.wikipedia.org/wiki/Oxygen-evolving_complex

    The oxygen-evolving complex (OEC), also known as the water-splitting complex, is a water-oxidizing enzyme involved in the photo-oxidation of water during the light reactions of photosynthesis. [3] OEC is surrounded by 4 core proteins of photosystem II at the membrane-lumen interface.

  5. Heterogeneous water oxidation - Wikipedia

    en.wikipedia.org/wiki/Heterogeneous_Water_Oxidation

    Of the two half reactions, the oxidation step is the most demanding because it requires the coupling of 4 electron and proton transfers and the formation of an oxygen-oxygen bond. This process occurs naturally in plants photosystem II to provide protons and electrons for the photosynthesis process and release oxygen to the atmosphere, [ 1 ] as ...

  6. Evolution of photosynthesis - Wikipedia

    en.wikipedia.org/wiki/Evolution_of_photosynthesis

    Oxygenic photosynthesis uses water as an electron donor, which is oxidized to molecular oxygen (O 2) in the photosynthetic reaction center. The biochemical capacity for oxygenic photosynthesis evolved in a common ancestor of extant cyanobacteria. [11] The first appearance of free oxygen in the atmosphere is sometimes referred to as the oxygen ...

  7. Evolution of metal ions in biological systems - Wikipedia

    en.wikipedia.org/wiki/Evolution_of_Metal_Ions_in...

    The oxygen-evolving complex (OEC) is a critical component of photosystem II contained in the thylakoid membranes of chloroplasts; it is responsible for terminal photooxidation of water during light reactions. [11] The incorporation of Mn in proteins allowed the complexes the ability to reduce reactive oxygen species in Mn-superoxide dismutase ...

  8. Manganese in biology - Wikipedia

    en.wikipedia.org/wiki/Manganese_in_biology

    Manganese is also important in photosynthetic oxygen evolution in chloroplasts in plants. The oxygen-evolving complex (OEC) is a part of photosystem II contained in the thylakoid membranes of chloroplasts; it is responsible for the terminal photooxidation of water during the light reactions of photosynthesis , and has a metalloenzyme core ...

  9. Dioxygen in biological reactions - Wikipedia

    en.wikipedia.org/wiki/Dioxygen_in_biological...

    After being carried in blood to a body tissue in need of oxygen, O 2 is handed off from the heme group to monooxygenase, an enzyme that also has an active site with an atom of iron. [9] Monooxygenase uses oxygen for many oxidation reactions in the body. Oxygen that is suspended in the blood plasma equalizes into the tissue according to Henry's law.