Protein Variants | Comment | Organism |
---|---|---|
C76A | mutant of subunit NqrF which lacks the 2Fe-2S-center cofactor and shows a 90% decrease in menadione reductase activity | Vibrio cholerae serotype O1 |
D346A | the redox reaction in this mutant is significantly inhibited and the Na+ sensitivity of CoQ reduction is completely abolished, while the apparent affinity for Na+ is essentially unchanged. In D346A, electron transfer between FMN from subunit NqrB and riboflavin is inhibited | Vibrio cholerae serotype O1 |
D397A | the reduction of subunit NqrB mutant D397A by NADH is very similar to the reduction of wild type enzyme but does not show sensitivity to Na+, and the rate of the stable neutral riboflavin radical to riboflavin-H2 is decreased 3fold. In NqrB-D397A, the reaction takes place in two steps: rapid oxidation of riboflavin and the two FMNs, followed by oxidation of FAD, at a 16fold lower rate | Vibrio cholerae serotype O1 |
T225Y | the mutant lacks FMN from subunit NqrC and is unable to produce an electrochemical potential under either partial or multiple turnover conditions | Vibrio cholerae serotype O1 |
T236Y | the mutant lacks FMN from subunit NqrB and is unable to produce an electrochemical potential under either partial or multiple turnover conditions | 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 | - |
- |
- |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
NADH + H+ + ubiquinone + n Na+/in | - |
Vibrio cholerae serotype O1 | NAD+ + ubiquinol + n Na+/out | - |
? |
Synonyms | Comment | Organism |
---|---|---|
Na+-NQR | - |
Vibrio cholerae serotype O1 |
Na+-pumping NADH:quinone oxidoreductase | - |
Vibrio cholerae serotype O1 |
sodium pumping NADH:quinone oxidoreductase | - |
Vibrio cholerae serotype O1 |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
FAD | contains one noncovalently bound FAD | Vibrio cholerae serotype O1 | |
FMN | contains two FMNs covalently bound to the NqrB and NqrC subunits | Vibrio cholerae serotype O1 | |
NADH | - |
Vibrio cholerae serotype O1 | |
riboflavin | contains one noncovalently bound riboflavin | Vibrio cholerae serotype O1 | |
[2Fe-2S]-center | contains one 2Fe-2S-center | Vibrio cholerae serotype O1 |
General Information | Comment | Organism |
---|---|---|
metabolism | Na+-NQR couples the free energy of electron transfer reactions to electrogenic pumping of sodium across the cell membrane. Na+ uptake by Na+-NQR is a nonelectrogenic process that occurs upon electron transfer from the 2Fe-2S-center to FMN of subunit NqrC, while the electrogenic transport of Na+ across the membrane, and likely release into solution, occurs upon electron transfer from FMN of subunit NqrB to riboflavin | Vibrio cholerae serotype O1 |