Desulfoferrodoxin of Clostridium acetobutylicum functions as a superoxide reductase.
Desulfoferrodoxin (cac2450) of Clostridium acetobutylicum was purified after overexpression in E. coli. In an in vitro assay the enzyme exhibited superoxide reductase activity with rubredoxin (cac2778) of C. acetobutylicum as the proximal electron donor. Rubredoxin was reduced by ferredoxin:NADP(+) reductase from spinach and NADPH. The superoxide anions, generated from dissolved oxygen using Xanthine and Xanthine oxidase, were reduced to hydrogen peroxide. Thus, we assume that desulfoferrodoxin is the key factor in the superoxide reductase dependent part of an alternative pathway for detoxification of reactive oxygen species in this obligate anaerobic bacterium.
Riebe
Oliver
O
University of Rostock, Institute of Biological Sciences, Division of Microbiology, Albert-Einstein-Strasse 3, D-18051, Rostock, Germany.
Fischer
Ralf-Jörg
RJ
Bahl
Hubert
H
D001426:Bacterial Proteins / Q000502:physiology*; D046969:Clostridium acetobutylicum / Q000201:enzymology*; D045304:Cytochromes c / Q000378:metabolism; D005288:Ferredoxins / Q000302:isolation & purification / Q000502:physiology*; D006861:Hydrogen Peroxide / Q000378:metabolism; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000502:physiology*; D017382:Reactive Oxygen Species / Q000378:metabolism; D012416:Rubredoxins / Q000302:isolation & purification; D013482:Superoxide Dismutase / Q000378:metabolism; D013481:Superoxides / Q000378:metabolism
D001426:Bacterial Proteins; D005288:Ferredoxins; D017382:Reactive Oxygen Species; D012416:Rubredoxins; C066602:desulfoferrodoxin; D013481:Superoxides; D045304:Cytochromes c; D006861:Hydrogen Peroxide; D010088:Oxidoreductases; C121849:superoxide reductase; D013482:Superoxide Dismutase