The Competition Between Chemistry and Biology in Assembling Iron–Sulfur Derivatives: Molecular Structures and Electrochemistry. Part VI. {[Fe 4 S 4 ](S γ Cys ) 3 (nonthiolate ligand)} Proteins

Within a couple of years we have planned to systematically update structure/electrochemistry of the different classes of metalloproteins harboring iron–sulfur clusters. In this picture we have so far dealt with {Fe(Cys)4}, {[Fe2S2](Cys)4}, {[Fe2S2](Cys)3(X)} (X = Asp, Arg, His), {[Fe2S2](Cys)2(His)2}, {[Fe3S4](Cys)3}, and {[Fe4S4](Cys)4} cores. Since a significant number of structurally characterized [4Fe–4S] proteins harbor {[Fe4S4](SγCys)3(nonthiolate ligand)} iron–sulfur centers, the aim of the present review paper is to complement our paper review on {[Fe4S4](Cys)4} cores with structure and electrochemistry of {[Fe4S4](SγCys)3(nonthiolate ligand)} proteins in order to gain a panoramic overview of the state-of-the-art of structure/electrochemistry of all the [4Fe–4S] proteins (excluding obviously those proteins which harbor mixed iron–sulfur clusters such as [4Fe–4S] + [2Fe–2S], [4Fe–4S] + [3Fe–4S], [4Fe–4S] + [3Fe–4S] + [2Fe–2S], and [4Fe–4S] + [3Fe–4S] + [4Fe–3S]).