Purification and characterization of a 7Fe ferredoxin from a thermophilic hydrogen-oxidizing bacterium, Bacillus schlegelii.
A ferredoxin (Fd) was purified from a thermophilic hydrogen-oxidizing bacterium, Bacillus schlegelii. This ferredoxin was a monomer with apparent molecular weight of 13,000 and contained 7 mol Fe/mol ferredoxin. The oxidized ferredoxin showed the characteristic EPR spectrum for [3Fe-4S]1+ (1.2 spin/mol Fd). This signal disappeared upon reduction with dithionite and new signals due to [3Fe-4S]0 and [4Fe-4S]1+ (0.7 spin/mol Fd) appeared. The quantitation of EPR signals and the iron content reveal that B. schlegelii ferredoxin contains one [3Fe-4S]1+/0 and one [4Fe-4S]2+/1+ cluster. The ferredoxin has the characteristic distribution of cysteines (-Cys8-X7-Cys16-X3-Cys20-Pro-) for 7Fe ferredoxins in the N-terminus.
Aono
S
S
Department of Bioengineering, Tokyo Institute of Technology, Kanagawa.
Kurita
H
H
Uno
S
S
Okura
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I
D000595:Amino Acid Sequence; D001407:Bacillus / Q000737:chemistry*; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D003545:Cysteine / Q000032:analysis; D004578:Electron Spin Resonance Spectroscopy; D004591:Electrophoresis, Polyacrylamide Gel; D005288:Ferredoxins / Q000737:chemistry* / Q000302:isolation & purification; D007501:Iron / Q000032:analysis*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D011487:Protein Conformation; D013053:Spectrophotometry
D005288:Ferredoxins; D007501:Iron; D003545:Cysteine