Term: photosystem
https://doi.org/10.1351/goldbook.PT06782

Definition:
A membrane-bound complex in plants and photosynthetic bacteria, responsible for light-harvesting and primary electron transfer. Comprises light-harvesting pigments such as chlorophyll; a primary electron-transfer centre, and secondary electron carriers. In green plant photosynthesis, Photosystem I transfers electrons from plastocyanin to a [2Fe-2S] ferredoxin, and contains iron-sulfur proteins. Photosystem II transfers electrons from the oxygen-evolving complex to plastoquinone, and contains an iron centre.

Related Terms:
1) membrane (http://doi.org/10.1351/goldbook.MT06878).
2) electron transfer (http://doi.org/10.1351/goldbook.E02011).
3) photosynthesis (http://doi.org/10.1351/goldbook.P04655).
4) ferredoxin (http://doi.org/10.1351/goldbook.FT06771).
5) iron-sulfur proteins (http://doi.org/10.1351/goldbook.IT06780).

Source: PAC, 1997, 69, 1251. 'Glossary of terms used in bioinorganic chemistry (IUPAC Recommendations 1997)' on page 1292 (https://doi.org/10.1351/pac199769061251)

Citation: 'photosystem' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.PT06782

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