IUBMB Enzyme Nomenclature


Accepted name: thiosulfate reductase (quinone)

Reaction: sulfite + hydrogen sulfide + a quinone = thiosulfate + a quinol

Other name(s): phsABC (gene names)

Systematic name: sulfite,hydrogen sulfide:quinone oxidoreductase

Comments: The enzyme, characterized from the bacterium Salmonella enterica, is similar to EC, formate dehydrogenase-N. It contains a molybdopterin-guanine dinucleotide, five [4Fe-4S] clusters and two heme b groups. The reaction occurs in vivo in the direction of thiosulfate disproportionation, which is highly endergonic. It is driven by the proton motive force that occurs across the cytoplasmic membrane.

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:


1. Kwan, H.S. and Barrett, E.L. Map locations and functions of Salmonella typhimurium men genes. J. Bacteriol. 159 (1984) 1090-1092. [PMID: 6384182]

2. Clark, M.A. and Barrett, E.L. The phs gene and hydrogen sulfide production by Salmonella typhimurium. J. Bacteriol. 169 (1987) 2391-2397. [PMID: 3108233]

3. Alami, N. and Hallenbeck, P.C. Cloning and characterization of a gene cluster, phsBCDEF, necessary for the production of hydrogen sulfide from thiosulfate by Salmonella typhimurium. Gene 156 (1995) 53-57. [PMID: 7737516]

4. Heinzinger, N.K., Fujimoto, S.Y., Clark, M.A., Moreno, M.S. and Barrett, E.L. Sequence analysis of the phs operon in Salmonella typhimurium and the contribution of thiosulfate reduction to anaerobic energy metabolism. J. Bacteriol. 177 (1995) 2813-2820. [PMID: 7751291]

5. Stoffels, L., Krehenbrink, M., Berks, B.C. and Unden, G. Thiosulfate reduction in Salmonella enterica is driven by the proton motive force. J. Bacteriol. 194 (2012) 475-485. [PMID: 22081391]

[EC created 2016, modified 2017]

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