Univ. Grenoble Alpes, CNRS, CEA, IRIG, Laboratoire de Chimie et Biologie des Métaux, Grenoble F-38000, France.
Laboratoire de Chimie Bactérienne, UMR7243 Aix-Marseille Université CNRS, 31 Chemin Joseph Aiguier, Marseille 13009, France.
Inorg Chem. 2024 May 13;63(19):8730-8738. doi: 10.1021/acs.inorgchem.4c00304. Epub 2024 Apr 30.
Iron-sulfur (Fe-S) clusters are essential inorganic cofactors dedicated to a wide range of biological functions, including electron transfer and catalysis. Specialized multiprotein 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 SufBCD scaffold from by XAS and Mössbauer, UV-visible absorption, and EPR spectroscopies. Interestingly, we propose that SufBCD harbors two iron-sulfur-containing species, a [2Fe-2S] cluster and an as-yet unidentified species. Mutagenesis and biochemistry were used to propose amino acid ligands for the [2Fe-2S] cluster, supporting the hypothesis that both SufB and SufD are involved in the Fe-S cluster ligation. The [2Fe-2S] cluster can be transferred to ferredoxin in agreement with the SufBCD scaffold function. These results are discussed in the context of Fe-S cluster biogenesis.
铁硫 (Fe-S) 簇是一类重要的无机辅因子，参与多种生物学功能，包括电子传递和催化。各种生物体中都存在专门的多蛋白机器来支持其生物合成。这些机器包含一个支架蛋白，Fe-S 簇在被转移到细胞靶标之前就在该蛋白上组装。在这里，我们通过 X 射线吸收光谱、穆斯堡尔谱、紫外可见吸收光谱和电子顺磁共振光谱首次描述了来自 的 SufBCD 支架的天然 Fe-S 簇的特性。有趣的是，我们提出 SufBCD 含有两种含铁硫的物质，一个 [2Fe-2S] 簇和一个尚未确定的物质。突变和生化分析用于提出 [2Fe-2S] 簇的氨基酸配体，支持 SufB 和 SufD 都参与 Fe-S 簇配位的假说。[2Fe-2S] 簇可以与铁氧还蛋白转移，这与 SufBCD 支架的功能一致。这些结果在 Fe-S 簇生物发生的背景下进行了讨论。
