InterPro domain: IPR016092

Proteins in this entry include HesB, IscA, SufA and ErpA, and appear to be scaffold proteins upon which 2Fe-2S clusters are assembled and subsequently transferred to acceptor proteins.

Several multiprotein complexes, referred to as ISC, SUF, and NIF, are known to be necessary for building and inserting Fe-S clusters into cellular targets [ 1 ]. The HesB proteins are associated with the nif gene cluster. The Escherichia coli SufA protein is associated with SufS, a NifS homologue, and SufD which are involved in the FeS cluster assembly of the FhnF protein [ 2 ]. The Azotobacter protein IscA (homologues of which are also found in E. coli) is associated which IscS, another NifS homologue, and IscU, a NifU homologue, as well as other factors consistent with a role in FeS cluster chemistry [ 3 ]. ErpA is required, together with IscA, for the delivery of iron-sulphur clusters to the hydrogen-oxidizing [NiFe]-hydrogenases in Escherichia coli [ 4 , 5 ].

1. Iron-sulfur protein biogenesis in eukaryotes: components and mechanisms. Annu. Rev. Cell Dev. Biol. 22, 457-86
2. SufS is a NifS-like protein, and SufD is necessary for stability of the [2Fe-2S] FhuF protein in Escherichia coli. J. Bacteriol. 181, 3307-9
3. Assembly of iron-sulfur clusters. Identification of an iscSUA-hscBA-fdx gene cluster from Azotobacter vinelandii. J. Biol. Chem. 273, 13264-72
4. ErpA, an iron sulfur (Fe S) protein of the A-type essential for respiratory metabolism in Escherichia coli. Proc. Natl. Acad. Sci. U.S.A. 104, 13626-31
5. Delivery of iron-sulfur clusters to the hydrogen-oxidizing [NiFe]-hydrogenases in Escherichia coli requires the A-type carrier proteins ErpA and IscA. PLoS ONE 7, e31755