Purification and properties of ferredoxin and rubredoxin from Butyribacterium methylotrophicum.
AUTOR(ES)
Saeki, K
RESUMO
A ferredoxin and a rubredoxin from Butyribacterium methylotrophicum, which displays a carbonyl-dependent acetyl-coenzyme A synthesis, were purified to electrophoretic homogeneity. The two electron carriers showed absorption spectra similar to those in Clostridium species. The ferredoxin displayed absorption peaks at 280 and 391 nm, while rubredoxin displayed absorption peaks at 279, 382, and 482 nm. Minimum molecular weights calculated from the respective amino acid compositions were 5,727 for ferredoxin and 5,488 for rubredoxin, excluding iron and inorganic sulfur atoms. Both electron carriers were isolated as monomers, according to gel-filtration data. Electron spin resonance analysis revealed that the ferredoxin was a 2[4Fe-4S]-type and that both clusters had a midpoint redox potential value of -410 mV, whereas rubredoxin contained one acid-stable iron and had a redox value of -40 mV. The coupling of these electron carriers to hydrogenase and carbon monoxide dehydrogenase activities was investigated. Rubredoxin showed higher activity towards carbon monoxide dehydrogenase, whereas ferredoxin showed higher activity towards hydrogenase.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=210274Documentos Relacionados
- Carbon monoxide metabolism of the methylotrophic acidogen Butyribacterium methylotrophicum.
- Anaerobic catabolism of formate to acetate and CO2 by Butyribacterium methylotrophicum.
- Metabolism of H2-CO2, methanol, and glucose by Butyribacterium methylotrophicum.
- Purification and characterization of cytochrome c3, ferredoxin, and rubredoxin isolated from Desulfovibrio desulfuricans Norway.
- Amino Acid Composition of Ferredoxin and Rubredoxin Isolated from Desulfovibrio gigas