A multidisciplinary analysis of the as-isolated Escherichia coli SufBC2D complex reveals the presence of two new iron-sulfur clusters

Veronesi, G.; Perard, J.; Clemancey, M.; Gerez, C.; Duverger, Y.; Kieffer, I.; Barras, F.; Gambarelli, S.; Blondin, G.; ollagnier de choudens, s.

doi:10.1101/2022.03.29.486248

bioRxiv · 10.1101/2022.03.29.486248

A multidisciplinary analysis of the as-isolated Escherichia coli SufBC2D complex reveals the presence of two new iron-sulfur clusters

Veronesi, G.·Perard, J.·Clemancey, M.·Gerez, C.·Duverger, Y.·Kieffer, I.·Barras, F.·Gambarelli, S.·Blondin, G.·ollagnier de choudens, s.

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Abstract

Iron-sulfur (Fe-S) clusters are essential inorganic cofactors dedicated to a wide range of biological functions including electron transfer and catalysis. Specialized multi-protein machineries present in all types of organisms support their biosynthesis. These machineries encompass a scaffold protein on which Fe-S clusters are assembled before being transferred to cellular targets. Here, we describe the first characterization of the native Fe-S cluster of the anaerobically purified SufBC2D scaffold from Escherichia coli by XAS, Mossbauer, UV-visible absorption and EPR spectroscopy. Interestingly, we propose that SufBC2D harbors two types of Fe-S cluster, a [2Fe-2S] cluster with an unprecedented usual coordination and a previously unreported [3Fe-3S] cluster. These data combined with mutagenesis and biochemistry allow to propose ligands for these clusters. These results support the hypothesis that both SufB and SufD are involved in Fe-S cluster ligation and are discussed in the context of Fe-S cluster biogenesis where both [2Fe-2S] and [4Fe-4S] clusters need to mature cellular Fe-S protein targets.

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Veronesi, G., Perard, J., Clemancey, M., Gerez, C., Duverger, Y., Kieffer, I., Barras, F., Gambarelli, S., Blondin, G., ollagnier de choudens, s.. 2022-03-29. A multidisciplinary analysis of the as-isolated Escherichia coli SufBC2D complex reveals the presence of two new iron-sulfur clusters. https://doi.org/10.1101/2022.03.29.486248

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