Cloned (Comment) | Organism |
---|---|
sequence comparisons and phylogenetic analysis | Aquifex aeolicus |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
2-heptyl-4-hydroxyquinoline N-oxide | HQNO, complete inhibition at 0.01 mM | Aquifex aeolicus | |
antimycin A | 55% inhibition at 0.027 mM | Aquifex aeolicus |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
additional information | - |
additional information | Michaelis-Menten kinetics | Aquifex aeolicus | |
0.0026 | - |
sulfite | pH 8.3, 55°C, with decyl-ubiquinone | Aquifex aeolicus | |
0.034 | - |
sulfite | pH 8.3, 55°C, with Nitro-blue tetrazolium | Aquifex aeolicus |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
membrane | the enzyme is membrane-bound and quinone reactive (via the SoeC subunit), facing the cytoplasm where SoeB (a module that carries FeeS centers) and the SoeA (the Mo-carrying catalytic subunit) are exposed. The enzyme is a large membrane-bound complex, formerly called SreABC | Aquifex aeolicus | 16020 | - |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Molybdenum | required, enzyme Soe contains, in its active site, a molybdenum atom coordinated by two molecules of pyranopterin guanosine dinucleotide (therefore also named Mo-bisPGD enzymes) rather than a single pyranopterin | Aquifex aeolicus |
Molecular Weight [Da] | Molecular Weight Maximum [Da] | Comment | Organism |
---|---|---|---|
211000 | - |
monomeric trimer, gel filtration | Aquifex aeolicus |
389000 | - |
dimeric trimer, gel filtration | Aquifex aeolicus |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
sulfite + decyl-ubiquinone + H2O | Aquifex aeolicus | - |
sulfate + decyl-ubiquinol | - |
r |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Aquifex aeolicus | O67280 AND O67279 AND O67278 | subunits SreA, SreB, and SreC | - |
Purification (Comment) | Organism |
---|---|
native enzyme 23fold from cell membranes via solubilization by various non-ionic detergents, centrifugation at 40000 x g, followed by anion exchange chromatography, ultrafiltration, and gel filtration | Aquifex aeolicus |
Specific Activity Minimum [µmol/min/mg] | Specific Activity Maximum [µmol/min/mg] | Comment | Organism |
---|---|---|---|
84.2 | - |
purified enzyme, substrate sulfite, pH 8.3, 55°C | Aquifex aeolicus |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
additional information | the enzyme catalyzes sulfite oxidation using Nitro-blue tetrazolium as artificial electron acceptor at pH 7.8 and 60°C. The enzyme specifically oxidizes sulfite but can work in the reverse direction, reduction of sulfur or tetrathionate, using reduced methyl viologen (MV) as electron donor, thiosulfate is not able to act as an electron acceptor from MV, absence of reduction of thiosulfate by SoeABC. Oxidation of sodium tetrathionate by SoeABC is performed using DCPIP (2,6-dichlorophenolindophenol) in the presence or absence of phenazine methosulfate (PMS). No oxidation of sulfite, tetrathionate, polysulfide or thiosulfate, SoeABC seems therefore to oxidize sulfite specifically | Aquifex aeolicus | ? | - |
- |
|
sulfite + decyl-ubiquinone + H2O | - |
Aquifex aeolicus | sulfate + decyl-ubiquinol | - |
r | |
sulfur + reduced methyl viologen + H2O | - |
Aquifex aeolicus | H2S + oxidized methyl viologen | - |
? | |
tetrathionate + reduced methyl viologen + H2O | - |
Aquifex aeolicus | ? + oxidized methyl viologen | - |
? |
Subunits | Comment | Organism |
---|---|---|
hexamer | dimer of trimer (alphabetagamma)2 | Aquifex aeolicus |
Synonyms | Comment | Organism |
---|---|---|
quinone-reducing molybdenum sulfite dehydrogenase | - |
Aquifex aeolicus |
SoeABC | - |
Aquifex aeolicus |
SreABC | - |
Aquifex aeolicus |
sulfur reductase | - |
Aquifex aeolicus |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
55 | - |
oxidation reaction | Aquifex aeolicus |
55 | 70 | reduction reaction | Aquifex aeolicus |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
52.9 | - |
sulfite | pH 8.3, 55°C, with decyl-ubiquinone | Aquifex aeolicus | |
567 | - |
sulfite | pH 8.3, 55°C, with Nitro-blue tetrazolium | Aquifex aeolicus |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
7.8 | - |
cell membrane fraction, assay at | Aquifex aeolicus |
8.2 | - |
purified enzyme, reduction assay at | Aquifex aeolicus |
8.3 | - |
purified enzyme, oxidation reaction | Aquifex aeolicus |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
molybdenum cofactor | enzyme Soe contains, in its active site, a molybdenum atom coordinated by two molecules of pyranopterin guanosine dinucleotide (therefore also named Mo-bisPGD enzymes) rather than a single pyranopterin | Aquifex aeolicus |
General Information | Comment | Organism |
---|---|---|
evolution | phylogenetic tree of Mo-bisPGD enzymes involved in sulfur compounds conversion, phylogenetic analysis, overview | Aquifex aeolicus |
metabolism | SoeABC is involved in the sulfite oxidation in the marine hyperthermophilic bacterium Aquifex aeolicus | Aquifex aeolicus |
additional information | the SoeABC enzyme is a member of the DMSO-reductase family of molybdenum enzymes, or complex iron-sulfur molybdoenzymes (CISM) family | Aquifex aeolicus |
physiological function | electrons generated by sulfite oxidation in the cytoplasm enter the respiratory chain at the level of quinones | Aquifex aeolicus |
kcat/KM Value [1/mMs-1] | kcat/KM Value Maximum [1/mMs-1] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
16676.5 | - |
sulfite | pH 8.3, 55°C, with Nitro-blue tetrazolium | Aquifex aeolicus | |
20346 | - |
sulfite | pH 8.3, 55°C, with decyl-ubiquinone | Aquifex aeolicus |