Reaction: (1a) glutathione + sulfur = S-sulfanylglutathione (spontaneous)
(1b) S-sulfanylglutathione + O2 + H2O = glutathione + sulfite + 2 H+
Other name(s): sulfur oxygenase; sulfur:oxygen oxidoreductase
Systematic name: S-sulfanylglutathione:oxygen oxidoreductase
Comments: An iron protein. Glutathione (GSH) plays a catalytic role in elemental sulfur activation, but is not consumed during the enzymic reaction. GSH and elemental sulfur react non-enzymically to yield S-sulfanylglutathione and it is only in this form that the sulfur can be oxidized to yield sulfite. The sulfite can be further converted into sulfate, thiosulfate or S-sulfoglutathione (GSSO3-) non-enzymically [2].
Links to other databases: BRENDA, EXPASY, KEGG, CAS registry number: 37256-58-9
References:
1. Suzuki, I. and Silver, M. The initial product and properties of the sulfur-oxidizing enzyme of thiobacilli. Biochim. Biophys. Acta 122 (1966) 22-33. [PMID: 5968172]
2. Rohwerder, T. and Sand, W. The sulfane sulfur of persulfides is the actual substrate of the sulfur-oxidizing enzymes from Acidithiobacillus and Acidiphilium spp. Microbiology 149 (2003) 1699-1710. [PMID: 12855721]