Ligands to the 2Fe iron-sulfur center in succinate dehydrogenase.
Membrane-bound succinate oxidoreductases are flavoenzymes containing one each of a 2Fe, a 3Fe and a 4Fe iron-sulfur center. Amino acid sequence homologies indicate that all three centers are located in the Ip (B) subunit. From polypeptide and gene analysis of Bacillus subtilis succinate dehydrogenase-defective mutants combined with earlier EPR spectroscopic data, we show that four conserved cysteine residues in the first half of Ip are the ligands to the [2Fe-2S] center. These four residues have previously been predicted to be the ligands. Our results also suggest that the N-terminal part of B. subtilis Ip constitutes a domain which can incorporate separately the 2Fe center and interact with Fp, the flavin-containing subunit of the dehydrogenase.
AEvarsson
A
A
Department of Microbiology, University of Lund, Sweden.
Hederstedt
L
L
D001412:Bacillus subtilis / Q000201:enzymology / Q000235:genetics; D003001:Cloning, Molecular; D003062:Codon; D004262:DNA Restriction Enzymes; D004269:DNA, Bacterial / Q000235:genetics; D004578:Electron Spin Resonance Spectroscopy; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000235:genetics; D007163:Immunosorbent Techniques; D007501:Iron / Q000378:metabolism*; D007506:Iron-Sulfur Proteins / Q000378:metabolism*; D008667:Metalloproteins / Q000378:metabolism*; D009154:Mutation; D010957:Plasmids; D013385:Succinate Dehydrogenase / Q000235:genetics / Q000378:metabolism*; D013455:Sulfur / Q000378:metabolism*
D003062:Codon; D004269:DNA, Bacterial; D007506:Iron-Sulfur Proteins; D008667:Metalloproteins; D013455:Sulfur; D007501:Iron; D013385:Succinate Dehydrogenase; D004262:DNA Restriction Enzymes