Cloned (Comment) | Organism |
---|---|
expression of N-terminally His6-tagged full-length enzyme and large subunit NqrA in Escherichia coli strain BL21(DE3) | Vibrio cholerae serotype O1 |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
2,5-dibromo-3-methyl-6-isopropyl-4-benzoquinone | a known inhibitor of the bc1 and b6f complexes found in mitochondria and chloroplasts, also inhibits quinone reduction by the Na+-NQR in a mixed inhibition mode. It does not just act as a simple competitor or redox mediator at the quinol oxidase site, but also as an antagonist to ubiquinone, inducing a redox bypass of the respiratory chain. The compound both acts as an inhibitor and as an alternative substrate of the Na+-NQR of Vibrio cholerae by a specific interaction with the NqrA subunit of the complex | Vibrio cholerae serotype O1 | |
2-n-heptyl-4-hydroxyquinoline N-oxide | - |
Vibrio cholerae serotype O1 | |
korormicin | - |
Vibrio cholerae serotype O1 |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
additional information | - |
additional information | Michaelis-Menten kinetics in the absence of 2,5-dibromo-3-methyl-6-isopropyl-4-benzoquinone | Vibrio cholerae serotype O1 | |
0.0245 | - |
ubiquinone | pH 7.5, 25°C, quinol formation | Vibrio cholerae serotype O1 | |
0.0296 | - |
NADH | pH 7.5, 25°C, NADH oxidation | Vibrio cholerae serotype O1 |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
membrane | - |
Vibrio cholerae serotype O1 | 16020 | - |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Fe2+ | 2 [2Fe-2S] clusters iin the NqrF subunit | Vibrio cholerae serotype O1 |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
NADH + H+ + ubiquinone + n Na+/in | Vibrio cholerae serotype O1 | - |
NAD+ + ubiquinol + n Na+/out | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Vibrio cholerae serotype O1 | - |
- |
- |
Purification (Comment) | Organism |
---|---|
recombinant N-terminally His6-tagged full-length enzyme and large subunit NqrA from Escherichia coli strain BL21(DE3) by nickel affinity chromatography and gel filtration | Vibrio cholerae serotype O1 |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
additional information | 2,5-dibromo-3-methyl-6-isopropyl-4-benzoquinone both acts as an inhibitor and as an alternative substrate of the Na+-NQR of Vibrio cholerae by a specific interaction with the NqrA subunit of the complex | Vibrio cholerae serotype O1 | ? | - |
? | |
NADH + H+ + ubiquinone + n Na+/in | - |
Vibrio cholerae serotype O1 | NAD+ + ubiquinol + n Na+/out | - |
? | |
NADH + H+ + ubiquinone-1 + n Na+/in | subunit NqrA of the Na+-NQR harbours a Q binding site, and the catalytic site of quinone reduction is located on NqrA | Vibrio cholerae serotype O1 | NAD+ + ubiquinol-1 + n Na+/out | - |
? |
Subunits | Comment | Organism |
---|---|---|
hexamer | the enzyme consists of four membrane-bound subunits NqrBCDE and the peripheral NqrF and NqrA subunits. The catalytic site of quinone reduction is located on subunit NqrA | Vibrio cholerae serotype O1 |
Synonyms | Comment | Organism |
---|---|---|
Na+-NQR | - |
Vibrio cholerae serotype O1 |
Na+-translocating NADH:quinone oxidoreductase | - |
Vibrio cholerae serotype O1 |
sodium ion-translocating NADH:quinone oxidoreductase | - |
Vibrio cholerae serotype O1 |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
25 | - |
assay at | Vibrio cholerae serotype O1 |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
7.5 | - |
assay at | Vibrio cholerae serotype O1 |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
FAD | non-covalently bound in the NqrF subunit | Vibrio cholerae serotype O1 | |
FMN | two covalently bound in subunits NqrB und NqrC | Vibrio cholerae serotype O1 | |
NADH | - |
Vibrio cholerae serotype O1 | |
riboflavin | one non-covalently bound in the subunit NqrB | Vibrio cholerae serotype O1 |
General Information | Comment | Organism |
---|---|---|
additional information | Na+-NQR is composed of six subunits NqrA-F and harbours at least five redox active cofactors: A non-covalently bound FAD and a 2Fe-2S cluster in the NqrF subunit, two covalently bound FMNs. The catalytic site of quinone reduction is located on NqrA. The two ligands bind to an extended binding pocket in direct vicinity to each other | Vibrio cholerae serotype O1 |
physiological function | the enzyme exploits the free energy liberated during oxidation of NADH with ubiquinone to pump sodium ions across the cytoplasmic membrane | Vibrio cholerae serotype O1 |