EC Number | Inhibitors | Comment | Organism | Structure |
---|---|---|---|---|
3.5.1.78 | H2O2 | 50% inhibition with 0.25 mM. Inactivation is above 95% with 0.5 mM H2O2 for 5 min. Cysteine thiol of the GspSA amidase active-site nucleophile Cys59 is transiently inactivated by H2O2 oxidation to sulfenic acid which leads to an accumulation of glutathionylspermidine and an increased level of glutathionylspermidine S-thiolated proteins after oxidative stress. The hypersensitivities of GspSA and GspSA/glutaredoxin null mutants to H2O2 support the idea that GspSA and glutaredoxin act synergistically to regulate the redox environment of Escherichia coli | Escherichia coli K-12 | |
6.3.1.8 | additional information | H2O2 leads to inhibition of the amidase activity, while the glutathionylspermidine synthase activity is almost unaffected | Escherichia coli |
EC Number | Organism | UniProt | Comment | Textmining |
---|---|---|---|---|
3.5.1.78 | Escherichia coli K-12 | P0AES0 | - |
- |
6.3.1.8 | Escherichia coli | P0AES0 | bifunctional glutathionylspermidine synthetase/amidase | - |
EC Number | Renatured (Comment) | Organism |
---|---|---|
3.5.1.78 | H2O2-mediated inactivation of the amidase activity can be recovered by the addition of 4 mM glutathione. ca. 80% of the enzyme activity are rescued | Escherichia coli K-12 |
EC Number | Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|---|
3.5.1.78 | glutathionylspermidine + H2O | - |
Escherichia coli K-12 | glutathione + spermidine | - |
? | |
3.5.1.78 | glutathionylspermidine disulfide + H2O | a coupled reaction of Gsp amidase and glutathione reductase | Escherichia coli K-12 | glutathione + ? | products of the coupled reaction of Gsp amidase and glutathione reductase: spermidine, glutathionylspermidine-glutathione mixed disulfide, and glutathione disulfide are generated | ? | |
3.5.1.78 | additional information | glutathionylspermidine S-thiolated peptides and proteins are tested as substrates. The protein substrates are treated with disulfide or biotinated glutathionylspermidine to generate biotin-labeled glutathionylspermidine S-thiolated proteins for the detection with an anti-biotin antibody after the reaction with the GspSA. A variety of glutathionylspermidine-derivatized substrates are hydrolyzed yielding spermidine and glutathione S-thiolated protein/peptides | Escherichia coli K-12 | ? | - |
? |
EC Number | Synonyms | Comment | Organism |
---|---|---|---|
3.5.1.78 | GSP amidase | - |
Escherichia coli K-12 |
3.5.1.78 | Gsp synthetase/amidase | bifunctional enzyme, EC 3.5.1.78 and EC 6.3.1.8 | Escherichia coli K-12 |
3.5.1.78 | GspSA | - |
Escherichia coli K-12 |
6.3.1.8 | GspSA | - |
Escherichia coli |
EC Number | General Information | Comment | Organism |
---|---|---|---|
6.3.1.8 | physiological function | hypersensitivities of the GspSA/glutaredoxin null mutants to H2O2 support the idea that GspSA and Grx synergistically defend against oxidative damage | Escherichia coli |