Reaction: tetrathionate + H2O = sulfate + thiosulfate + sulfur (overall reaction)
(1a) tetrathionate + H2O = disulfanidesulfonate + sulfate
(1b) disulfanidesulfonate = thiosulfate + sulfur (spontaneous)
Glossary: tetrathionate = disulfanedisulfonate
disulfanidesulfonate = disulfane monosulfonate
Other name(s): tetH (gene name)
Systematic name: tetrathionate sulfohydrolase
Comments: The enzyme, isolated from various acidophilic bacterial and archaeal species, has pH optima in the acidic range. The initial products are sulfate and disulfane monosulfonate. Though the latter is known to decompose spontaneously to sulfur and thiosulfate, it has been proposed that it can also react with itself, resulting in successive chain elongation leading to the production of elemental sulfur and sulfite.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:
References:
1. De Jong, G.A., Hazeu, W., Bos, P. and Kuenen, J.G. Isolation of the tetrathionate hydrolase from Thiobacillus acidophilus. Eur. J. Biochem. 243 (1997) 678-683. [PMID: 9057831]
2. Bugaytsova, Z. and Lindstrom, E.B. Localization, purification and properties of a tetrathionate hydrolase from Acidithiobacillus caldus. Eur. J. Biochem. 271 (2004) 272-280. [PMID: 14717695]
3. Kanao, T., Matsumoto, C., Shiraga, K., Yoshida, K., Takada, J. and Kamimura, K. Recombinant tetrathionate hydrolase from Acidithiobacillus ferrooxidans requires exposure to acidic conditions for proper folding. FEMS Microbiol. Lett. 309 (2010) 43-47. [PMID: 20546308]
4. Protze, J., Muller, F., Lauber, K., Nass, B., Mentele, R., Lottspeich, F. and Kletzin, A. An extracellular tetrathionate hydrolase from the thermoacidophilic archaeon Acidianus ambivalens with an activity optimum at pH 1. Front Microbiol. 2 (2011) 68. [PMID: 21747790]