EC Explorer

1.8.5.4

bacterial sulfide:quinone reductase

n HS^- + n quinone = polysulfide + n quinol

sqr (gene name), sulfide:quinone reductase (ambiguous), sulfide:quinone oxidoreductase

sulfide:quinone oxidoreductase (polysulfide-producing)

Contains FAD. Ubiquinone, plastoquinone or menaquinone can act as acceptor in different species. In some organisms the enzyme catalyses the formation of sulfur globules. It repeats the catalytic cycle without releasing the product, producing a polysulfide of up to 10 sulfur atoms. The reaction stops when the maximum length of the polysulfide that can be accommodated in the sulfide oxidation pocket is achieved. The enzyme also plays an important role in anoxygenic bacterial photosynthesis. cf. EC 1.8.5.8, sulfide quinone oxidoreductase.

created 2011, modified 2017, modified 2019