SufC: an unorthodox cytoplasmic ABC/ATPase required for [Fe-S] biogenesis under oxidative stress.
Proteins containing [Fe-S] clusters perform essential functions in all domains of life. Previously, we identified the sufABCDSE operon as being necessary for virulence of the plant pathogen Erwinia chrysanthemi. In addition, we collected preliminary evidence that the sufABCDSE operon might be involved in the assembly of [Fe-S] clusters. Of particular interest are the sufB, sufC and sufD genes, which are conserved among Eubacteria, Archaea, plants and parasites. The present study establishes SufC as an unorthodox ATPase of the ABC superfamily that is located in the cytosol, wherein it interacts with both SufB and SufD. Moreover, under oxidative stress conditions, SufC was found to be necessary for the activity of enzymes containing oxygen-labile [Fe-S] clusters, but dispensable for glutamate synthase, which contains an oxidatively stable [Fe-S] cluster. Lastly, we have shown SufBCD to be essential for iron acquisition via chrysobactin, a siderophore of major importance in virulence. We discuss a model wherein the SufBCD proteins contribute to bacterial pathogenicity via their role in the assembly of [Fe-S] clusters under oxidative stress and iron limitation.
Nachin
Laurence
L
LCB-CNRS, IBSM, 31 Chemin Joseph Aiguier, 13402 Marseille Cedex 20 and INRA/INA P-G, 16 rue Claude Bernard, 75231 Paris Cedex 05, France.
Loiseau
Laurent
L
Expert
Dominique
D
Barras
Frédéric
F
D000251:Adenosine Triphosphatases / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002458:Cell Fractionation; D003593:Cytoplasm / Q000737:chemistry / Q000378:metabolism; D016974:Dickeya chrysanthemi / Q000378:metabolism; D007501:Iron / Q000378:metabolism*; D007506:Iron-Sulfur Proteins / Q000235:genetics / Q000378:metabolism*; D005810:Multigene Family; D009876:Operon; D018384:Oxidative Stress; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism; D013455:Sulfur / Q000378:metabolism*; D020798:Two-Hybrid System Techniques
D001426:Bacterial Proteins; D007506:Iron-Sulfur Proteins; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; D013455:Sulfur; D007501:Iron; D000251:Adenosine Triphosphatases