SufA/IscA: reactivity studies of a class of scaffold proteins involved in [Fe-S] cluster assembly

被引:72
作者
Ollagnier-de-Choudens, S
Sanakis, Y
Fontecave, M
机构
[1] Univ Grenoble 1, Ctr Redox Biol, Lab Chim & Biochim, DRDC CB,CEA,CNRS,UMR 5047, F-38054 Grenoble 09, France
[2] NCSR Demokritos, Inst Mat Sci, Athens 15310, Greece
[3] Univ Ioannina, Dept Biol Applicat & Technol, GR-45110 Ioannina, Greece
来源
JOURNAL OF BIOLOGICAL INORGANIC CHEMISTRY | 2004年 / 9卷 / 07期
关键词
cluster assembly; iron-sulfur proteins; IscA protein; scaffold proteins; SufA protein;
D O I
10.1007/s00775-004-0581-9
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
IscA/SufA proteins belong to complex protein machineries which are involved in iron-sulfur cluster biosynthesis. They are defined as scaffold proteins from which preassembled clusters are transferred to target apoproteins. The experiments described here demonstrate that the transfer reaction proceeds in two observable steps: a first fast one leading to a protein-protein complex between the cluster donor (SufA/IscA) and the acceptor (biotin synthase), and a slow one consisting of cluster transfer leading to the apoform of the scaffold protein and the holoform of the target protein. Mutation of cysteines in the acceptor protein specifically inhibits the second step of the reaction, showing that these cysteines are involved in the cluster transfer mechanism but not in complex formation. No cluster transfer from IscA to IscU, another scaffold of the isc operon, could be observed, whereas IscU was shown to be an efficient cluster source for cluster assembly in IscA. Implications of these results are discussed.
引用
收藏
页码:828 / 838
页数:11
相关论文
共 60 条