Cloned (Comment) | Organism |
---|---|
expression in Escherichia coli | Trypanosoma brucei |
Protein Variants | Comment | Organism |
---|---|---|
C69S | about 5% of wild-type activity with substrate dithiothreitol, 0.5% with substrate rRNase | Trypanosoma brucei |
C72S | about 5% of wild-type activity with substrate dithiothreitol, 0.5% with substrate rRNase | Trypanosoma brucei |
additional information | replacement of either cysteine of the proximal disulfide, i.e. CIII or CIV with serine essentially abolishes activity both towards dithiothreitol and rRNase. Mutations of the terminal CxxC disulfide do not show significant loss of activity towards dithiothreitol or rRNase, the visible spectra of both CVS and CVIS mutants are comparable to that of the wild-type protein | Trypanosoma brucei |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.086 | - |
dithiothreitol | pH 7.5, 37°C | Trypanosoma brucei | |
0.36 | - |
rRNaseA | pH 7.5, 37°C | Trypanosoma brucei |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
membrane | type I membrane protein | Trypanosoma brucei | 16020 | - |
Molecular Weight [Da] | Molecular Weight Maximum [Da] | Comment | Organism |
---|---|---|---|
54000 | - |
PAGE | Trypanosoma brucei |
54300 | - |
analytical ultracentrifugation | Trypanosoma brucei |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Trypanosoma brucei | Q585M6 | - |
- |
Storage Stability | Organism |
---|---|
-20°C, 50 mM potassium phosphate buffer containing 1 mM EDTA, pH 7.5, stable for at least 1 year | Trypanosoma brucei |
4°C, 50 mM potassium phosphate buffer containing 1 mM EDTA, pH 7.5, stable for at least 6 months | Trypanosoma brucei |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
2 dithiothreitol + O2 | - |
Trypanosoma brucei | dithiothreitol disulfide + H2O2 | - |
? | |
2 glutathione + O2 | - |
Trypanosoma brucei | glutathione disulfide + H2O2 | - |
? | |
additional information | unfolded reduced proteins are more than 200fold more effective substrates on a per-thiol basis than glutathione, and some 10fold better than the parasite bis-glutathione analog, trypanothione. The CxxC motif in the single Trx domain is crucial for efficient catalysis of the oxidation of both reduced RNase and the model substrate dithiothreitol. The proximal disulfide CIII-CIV, which interacts with the flavin, is catalytically crucial. Turnover is limited by an internal redox step leading to 2-electron reduction of the FAD cofactor | Trypanosoma brucei | ? | - |
? | |
rRNaseA + O2 | - |
Trypanosoma brucei | ? + H2O2 | - |
? |
Subunits | Comment | Organism |
---|---|---|
monomer | 1 * 54000, SDS-PAGE | Trypanosoma brucei |
Synonyms | Comment | Organism |
---|---|---|
QSOX | - |
Trypanosoma brucei |
quiescin sulfhydryl oxidase | - |
Trypanosoma brucei |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
22 | - |
rRNaseA | pH 7.5, 37°C | Trypanosoma brucei | |
45 | - |
dithiothreitol | pH 7.5, 37°C | Trypanosoma brucei |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
7 | - |
- |
Trypanosoma brucei |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
FAD | turnover is limited by an internal redox step leading to 2-electron reduction of the FAD cofactor | Trypanosoma brucei |
kcat/KM Value [1/mMs-1] | kcat/KM Value Maximum [1/mMs-1] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
2.3 | - |
glutathione | pH 7.5, 37°C | Trypanosoma brucei | |
180 | - |
rRNaseA | pH 7.5, 37°C | Trypanosoma brucei | |
230 | - |
dithiothreitol | pH 7.5, 37°C | Trypanosoma brucei |