Molecular organization, biochemical function, cellular role and evolution of NfuA, an atypical Fe-S carrier

作者：Py Beatrice; Gerez Catherine; Angelini Sandra; Planel Remy; Vinella Daniel; Loiseau Laurent; Talla Emmanuel; Brochier Armanet Celine; Serres Ricardo Garcia; Latour Jean Marc; Ollagnier de Choudens Sandrine; Fontecave Marc; Barras Frederic^*

来源：Molecular Microbiology, 2012, 86(1): 155-171.

DOI：10.1111/j.1365-2958.2012.08181.x

Biosynthesis of ironsulphur (Fe-S) proteins is catalysed by multi-protein systems, ISC and SUF. However, non-ISC, non-SUF Fe-S biosynthesis factors have been described, both in prokaryotes and eukaryotes. Here we report in vitro and in vivo investigations of such a non-ISC, non SUF component, the Nfu proteins. Phylogenomic analysis allowed us to define four subfamilies. Escherichia coli NfuA is within subfamily II. Most members of this subfamily have a Nfu domain fused to a degenerate A-type carrier domain (ATC*) lacking Fe-S cluster co-ordinating Cys ligands. The Nfu domain binds a [4Fe-4S] cluster while the ATC* domain interacts with NuoG (a complex I subunit) and aconitase B (AcnB). In vitro, holo-NfuA promotes maturation of AcnB. In vivo, NfuA is necessary for full activity of complex I under aerobic growth conditions, and of AcnB in the presence of superoxide. NfuA receives Fe-S clusters from IscU/HscBA and SufBCD scaffolds and eventually transfers them to the ATCs IscA and SufA. This study provides significant information on one of the Fe-S biogenesis factors that has been often used as a building block by ISC and/or SUF synthesizing organisms, including bacteria, plants and animals.

• 出版日期2012-10
• 单位中国地震局