Sulfide dehydrogenase is identical with the SoxB protein of the thiosulfate-oxidizing enzyme system of Paracoccus denitrificans GB17

Abstract

Thiosulfate induced cells of Paracoccus denitrificans GB17 oxidize thiosulfate and sulfide to sulfate. A mutant carrying a Tn5-mob insertion in the soxB gene is unable to oxidize thiosulfate or sulfide suggesting a linkage of both activities. To test this assumption we have separated the components of the thiosulfate-oxidizing enzyme system of the wild-type by ion exchange chromatography. The SoxB protein coeluted with a highly active sulfide dehydrogenase. Analysis by polyacrylamide gel electrophoresis revealed one major protein of Mr 32k. Thus, the SoxB protein appeared to be identical with sulfide dehydrogenase. © 1994.