Iron-sulfur cluster biosynthesis: characterization of Schizosaccharomyces pombe Isa1.
Eukaryotic Isa1 is one of several mitochondrial proteins that have been implicated in Fe-S cluster assembly paths in vivo. We report the first biochemical characterization of an eukaryotic member of this family and discuss this in the context of results from in vivo studies and studies of bacterial homologues. Schizosaccharomyces pombe Isa1 is a multimeric protein carrying [2Fe-2S](2+) clusters that have been characterized by Mössbauer and optical spectroscopic studies. Complex formation with a redox-active ferredoxin has been identified through crosslinking experiments and the coordination chemistry and stability of the native clusters has been investigated through site-directed mutagenesis and spectroscopic analysis. Electronic supplementary material to this paper, containing Mössbauer and UV-visible spectra for mutant Isa1 proteins, can be obtained by using the Springer Link server located at http://dx.doi.org/10.1007/s00775-001-0330-2.
Wu
Gong
G
Evans Laboratory of Chemistry, Ohio State University, 100 West 18th Avenue, Columbus, OH 43210, USA.
Mansy
Sheref S
SS
Hemann
Craig
C
Hille
Russ
R
Surerus
Kristene K
KK
Cowan
J A
JA
D000409:Alanine; D000595:Amino Acid Sequence; D003001:Cloning, Molecular; D003432:Cross-Linking Reagents / Q000737:chemistry; D003545:Cysteine; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D004578:Electron Spin Resonance Spectroscopy; D004926:Escherichia coli / Q000737:chemistry; D005288:Ferredoxins / Q000737:chemistry; D007506:Iron-Sulfur Proteins / Q000096:biosynthesis*; D008969:Molecular Sequence Data; D009154:Mutation; D029701:Saccharomyces cerevisiae Proteins; D012568:Schizosaccharomyces / Q000235:genetics / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D015204:Spectroscopy, Mossbauer; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*
D003432:Cross-Linking Reagents; D004268:DNA-Binding Proteins; D005288:Ferredoxins; C410039:ISA1 protein, S cerevisiae; D007506:Iron-Sulfur Proteins; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D003545:Cysteine; D000409:Alanine