Purification and characterization of sulfide dehydrogenase from alkaliphilic chemolithoautotrophic sulfur-oxidizing bacteria

• Published in: FEBS letters Vol. 427; no. 1; pp. 11 - 14
• Main Authors: Sorokin, Dimitry Yu, de Jong, Govardus A.H, Robertson, Lesley A, Kuenen, Gijs J
• Format: Journal Article
• Language: English
• Published: England Elsevier B.V 01.05.1998
• Subjects: Alkaliphilic thiobacillus; Cytochrome c Group - isolation & purification; Membrane protein; Oxidation-Reduction; Oxidoreductases - isolation & purification; Sulfide dehydrogenase; Sulfides - metabolism; Sulfur metabolism; Thiobacillus - enzymology; Thiobacillus - metabolism; Thiosulfate; Thiosulfates - metabolism; Membrane protein; Alkaliphilic thiobacillus; Sulfur metabolism; Thiosulfate; Sulfide dehydrogenase
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/S0014-5793(98)00379-2

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 c 554. 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.