Purification and characterization of sulfide dehydrogenase from alkaliphilic chemolithoautotrophic sulfur-oxidizing bacteria.
Extracts of the alkaliphilic sulfur-oxidizing autotroph strain AL3 contained sulfide:cytochrome c oxidoreductase. This was active above pH 8, and was associated with the cell membranes. Although up to 60% of the initial activity was lost during Triton X-100 extraction, further purification resulted in an enzyme that catalyzed sulfide oxidation with horse heart cytochrome c. This enzyme was a 41 kDa protein containing heme c554. The optimum pH of the membrane bound enzyme was 9.0, but after extraction this fell to 8.0. The enzyme catalyzed a single electron oxidation of HS-. Hydrosulfide radical is therefore the most probable product.
Sorokin DYu
Institute of Microbiology, Russian Academy of Sciences, Moscow.
de Jong
G A
GA
Robertson
L A
LA
Kuenen
G J
GJ
D003574:Cytochrome c Group / Q000302:isolation & purification*; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000302:isolation & purification*; D013440:Sulfides / Q000378:metabolism; D013855:Thiobacillus / Q000201:enzymology* / Q000378:metabolism; D013885:Thiosulfates / Q000378:metabolism
D003574:Cytochrome c Group; D013440:Sulfides; D013885:Thiosulfates; D010088:Oxidoreductases; C064500:flavocytochrome c sulfide dehydrogenase