The SUF iron-sulfur cluster biosynthetic machinery: Sulfur transfer from the SUFS-SUFE complex to SUFA
The SUF iron-sulfur cluster biosynthetic machinery: Sulfur transfer from the SUFS-SUFE complex to SUFA
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DOI：
10.1016/j.febslet.2007.02.058
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发表时间：
2007-04-03
期刊：
影响因子：
3.5
通讯作者：
Fontecave, Marc
中科院分区：
文献类型：
--
作者：
Sendra, Maite;de Choudens, Sandrine Ollagnier;Fontecave, Marc
铁-硫簇的生物合成依赖于蛋白质机制，如ISC和SUF系统。该反应被认为意味着硫和铁原子的结合和簇在支架蛋白中的组装，然后簇转移到受体脱辅基蛋白。从大肠杆菌中提取的Sufa蛋白作为模型支架蛋白，通过质谱学分析表明，该蛋白能够与SufS-Sufe半胱氨酸脱硫酶体系提供的硫原子发生共价结合。对硫化Sufa进行的定点突变体研究和肽图谱实验表明，结合只发生在三个保守的半胱氨酸(cys50，cys114，cys116)上。相反，穆斯堡尔谱表明，它只与铁弱结合(K-a=5×10(5)M-1)，而不与保守的半胱氨酸特异结合。[Fe-S]团簇的穆斯堡尔谱表征表明，在电子源存在下，硫化SuFA与亚铁反应可以组装成[Fe-Fe3O4]团簇。(C)2007年欧洲生化学会联合会。爱思唯尔出版，版权所有。
Iron-sulfur cluster biosynthesis depends on protein machineries, such as the ISC and SUF systems. The reaction is proposed to imply binding of sulfur and iron atoms and assembly of the cluster within a scaffold protein followed by transfer of the cluster to recipient apoproteins. The SufA protein from Escherichia coli, used here as a model scaffold protein is competent for binding sulfur atoms provided by the SufS-SufE cysteine desulfurase system covalently as shown by mass spectrometry. Investigation of site-directed mutants and peptide mapping experiments performed on digested sulfurated SufA demonstrate that binding exclusively occurs at the three conserved cysteines (cys50, cys114, cys116). In contrast, it binds iron only weakly (K-a = 5 X 10(5) M-1) and not specifically to the conserved cysteines as shown by Mossbauer spectroscopy. [Fe-S] clusters, characterized by Mossbauer spectroscopy, can be assembled during reaction of sulfurated SufA with ferrous iron in the presence of a source of electrons. (c) 2007 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.