Term: iron-sulfur cluster
https://doi.org/10.1351/goldbook.IT06779

Definition:
A unit comprising two or more iron atoms and bridging sulfur ligands in an iron-sulfur protein. The recommended designation of a cluster consists of the iron and sulfur content, in square brackets, for example, [2Fe-2S], [3Fe-4S]. The possible oxidation levels are indicated by the net charge excluding the ligands, for example [4Fe-4S]2+; [4Fe-4S]+ or ([4Fe-4S]2+;1+) cluster.

Related Terms:
1) bridging (http://doi.org/10.1351/goldbook.B00741).
2) iron-sulfur protein (http://doi.org/10.1351/goldbook.IT06780).
3) cluster (http://doi.org/10.1351/goldbook.CT06769).
4) ligands (http://doi.org/10.1351/goldbook.L03518).
5) oxidation (http://doi.org/10.1351/goldbook.O04362).

Source: PAC, 1997, 69, 1251. 'Glossary of terms used in bioinorganic chemistry (IUPAC Recommendations 1997)' on page 1281 (https://doi.org/10.1351/pac199769061251)

Citation: 'iron-sulfur cluster' 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.IT06779

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