Rhodanese
| Rhodanese-like domain | |||||||||
|---|---|---|---|---|---|---|---|---|---|
 | |||||||||
| Identifiers | |||||||||
| Symbol | Rhodanese | ||||||||
| Pfam | PF00581 | ||||||||
| InterPro | IPR001763 | ||||||||
| PROSITE | PDOC00322 | ||||||||
| SCOP2 | 2ora / SCOPe / SUPFAM | ||||||||
| OPM superfamily | 413 | ||||||||
| OPM protein | 2mpn | ||||||||
| CDD | cd00158 | ||||||||
| Membranome | 571 | ||||||||
| |||||||||
Rhodanese, also known as rhodanase, thiosulfate sulfurtransferase, thiosulfate cyanide transsulfurase, and thiosulfate thiotransferase,[1] is a mitochondrial enzyme that detoxifies cyanide (CN−) by converting it to thiocyanate (SCN−).[2]
This reaction takes place in two steps. The diagram on the right shows the crystallographically-determined structure of rhodanese. In the first step, thiosulfate is reduced by the thiol group on cysteine-247 1, to form a persulfide and a sulfite 2. In the second step, the persulfide reacts with cyanide to produce thiocyanate, re-generating the cysteine thiol 1.[3]
This reaction is important for the treatment of exposure to cyanide, since the thiocyanate formed is around 1 / 200 as toxic.[4]:p. 15938 The use of thiosulfate solution as an antidote for cyanide poisoning is based on the activation of this enzymatic cycle.
Rhodanese shares evolutionary relationship with a large family of proteins, including
- Cdc25 phosphatase catalytic domain.
- non-catalytic domains of eukaryotic dual-specificity MAPK-phosphatases
- non-catalytic domains of yeast PTP-type MAPK-phosphatases
- non-catalytic domains of yeast Ubp4, Ubp5, Ubp7
- non-catalytic domains of mammalian Ubp-Y
- Drosophila heat shock protein HSP-67BB
- several bacterial cold-shock and phage shock proteins
- plant senescence associated proteins
- catalytic and non-catalytic domains of rhodanese[5]
Rhodanese has an internal duplication. This domain is found as a single copy in other proteins, including phosphatases and ubiquitin C-terminal hydrolases.[6]
Human proteins containing this domain[]
CDC25A; CDC25B; CDC25C; DUSP; DUSP1; DUSP10; DUSP16; DUSP2; DUSP4; DUSP5; DUSP6; DUSP7; ; ; MOCS3; MPST; ; ; TST; USP8;
Nomenclature[]
Although the standard nomenclature rules for enzymes indicate that their names are to end with the letters "-ase", rhodanese was first described in 1933,[7] prior to the 1955 establishment of the Enzyme Commission; as such, the older name had already attained widespread usage.
Thiosulfate sulfurtransferase[]
| thiosulfate sulfurtransferase | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Identifiers | |||||||||
| EC no. | 2.8.1.1 | ||||||||
| CAS no. | 9026-04-4 | ||||||||
| Databases | |||||||||
| IntEnz | IntEnz view | ||||||||
| BRENDA | BRENDA entry | ||||||||
| ExPASy | NiceZyme view | ||||||||
| KEGG | KEGG entry | ||||||||
| MetaCyc | metabolic pathway | ||||||||
| PRIAM | profile | ||||||||
| PDB structures | RCSB PDB PDBe PDBsum | ||||||||
| Gene Ontology | AmiGO / QuickGO | ||||||||
| |||||||||
In enzymology, a thiosulfate sulfurtransferase (EC 2.8.1.1) is an enzyme that catalyzes the chemical reaction
- thiosulfate + cyanide sulfite + thiocyanate
Thus, the two substrates of this enzyme are thiosulfate and cyanide, whereas its two products are sulfite and thiocyanate.
Nomenclature[]
This enzyme belongs to the family of transferases, specifically the sulfurtransferases, which transfer sulfur-containing groups. The systematic name of this enzyme class is thiosulfate:cyanide sulfurtransferase. Other names in common use include thiosulfate cyanide transsulfurase, thiosulfate thiotransferase, rhodanese, and rhodanase.
References[]
- ^ EC 2.8.1.1, at the International Union of Biochemistry and Molecular Biology
- ^ Cipollone R, Ascenzi P, Tomao P, Imperi F, Visca P (2008). "Enzymatic detoxification of cyanide: clues from Pseudomonas aeruginosa Rhodanese". Journal of Molecular Microbiology and Biotechnology. 15 (2–3): 199–211. doi:10.1159/000121331. PMID 18685272. S2CID 25431686.
- ^ Cipollone R, Ascenzi P, Tomao P, Imperi F, Visca P (2008). "Enzymatic detoxification of cyanide: clues from Pseudomonas aeruginosa Rhodanese". Journal of Molecular Microbiology and Biotechnology. 15 (2–3): 199–211. doi:10.1159/000121331. PMID 18685272. S2CID 25431686.
- ^ Jaszczak E, Polkowska Ż, Narkowicz S, Namieśnik J (July 2017). "Cyanides in the environment-analysis-problems and challenges". Environmental Science and Pollution Research International. 24 (19): 15929–15948. doi:10.1007/s11356-017-9081-7. PMC 5506515. PMID 28512706.
- ^ "Thiosulphate sulfurtransferase, conserved site (IPR001307)". EMBL-EBI. InterPro.
- ^ Gliubich F, Gazerro M, Zanotti G, Delbono S, Bombieri G, Berni R (August 1996). "Active site structural features for chemically modified forms of rhodanese". The Journal of Biological Chemistry. 271 (35): 21054–61. doi:10.1074/jbc.271.35.21054. PMID 8702871.
- ^ Cipollone R, Ascenzi P, Visca P (February 2007). "Common themes and variations in the rhodanese superfamily". IUBMB Life. 59 (2): 51–9. doi:10.1080/15216540701206859. PMID 17454295.
External links[]
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Wikimedia Commons has media related to Rhodanese. |
- Rhodanese at the US National Library of Medicine Medical Subject Headings (MeSH)
- EC 2.8
- Protein domains