BRENDA - Enzyme Database

Energy transducing redox steps of the Na+-pumping NADH:quinone oxidoreductase from Vibrio cholerae

Juarez, O.; Morgan, J.E.; Nilges, M.J.; Barquera, B.; Proc. Natl. Acad. Sci. USA 107, 12505-12510 (2010)

Data extracted from this reference:

Engineering
EC Number
Amino acid exchange
Commentary
Organism
7.2.1.1
C76A
mutant of subunit NqrF which lacks the 2Fe-2S-center cofactor and shows a 90% decrease in menadione reductase activity
Vibrio cholerae
7.2.1.1
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
7.2.1.1
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
7.2.1.1
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
7.2.1.1
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
Natural Substrates/ Products (Substrates)
EC Number
Natural Substrates
Organism
Commentary (Nat. Sub.)
Natural Products
Commentary (Nat. Pro.)
Organism (Nat. Pro.)
Reversibility
7.2.1.1
NADH + H+ + ubiquinone + n Na+/in
Vibrio cholerae
-
NAD+ + ubiquinol + n Na+/out
-
-
?
Organism
EC Number
Organism
Primary Accession No. (UniProt)
Commentary
Textmining
7.2.1.1
Vibrio cholerae
-
-
-
Substrates and Products (Substrate)
EC Number
Substrates
Commentary Substrates
Literature (Substrates)
Organism
Products
Commentary (Products)
Literature (Products)
Organism (Products)
Reversibility
7.2.1.1
NADH + H+ + ubiquinone + n Na+/in
-
713414
Vibrio cholerae
NAD+ + ubiquinol + n Na+/out
-
-
-
?
Cofactor
EC Number
Cofactor
Commentary
Organism
Structure
7.2.1.1
FAD
contains one noncovalently bound FAD
Vibrio cholerae
7.2.1.1
FMN
contains two FMNs covalently bound to the NqrB and NqrC subunits
Vibrio cholerae
7.2.1.1
NADH
-
Vibrio cholerae
7.2.1.1
riboflavin
contains one noncovalently bound riboflavin
Vibrio cholerae
7.2.1.1
[2Fe-2S]-center
contains one 2Fe-2S-center
Vibrio cholerae
Cofactor (protein specific)
EC Number
Cofactor
Commentary
Organism
Structure
7.2.1.1
FAD
contains one noncovalently bound FAD
Vibrio cholerae
7.2.1.1
FMN
contains two FMNs covalently bound to the NqrB and NqrC subunits
Vibrio cholerae
7.2.1.1
NADH
-
Vibrio cholerae
7.2.1.1
riboflavin
contains one noncovalently bound riboflavin
Vibrio cholerae
7.2.1.1
[2Fe-2S]-center
contains one 2Fe-2S-center
Vibrio cholerae
Engineering (protein specific)
EC Number
Amino acid exchange
Commentary
Organism
7.2.1.1
C76A
mutant of subunit NqrF which lacks the 2Fe-2S-center cofactor and shows a 90% decrease in menadione reductase activity
Vibrio cholerae
7.2.1.1
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
7.2.1.1
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
7.2.1.1
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
7.2.1.1
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
Natural Substrates/ Products (Substrates) (protein specific)
EC Number
Natural Substrates
Organism
Commentary (Nat. Sub.)
Natural Products
Commentary (Nat. Pro.)
Organism (Nat. Pro.)
Reversibility
7.2.1.1
NADH + H+ + ubiquinone + n Na+/in
Vibrio cholerae
-
NAD+ + ubiquinol + n Na+/out
-
-
?
Substrates and Products (Substrate) (protein specific)
EC Number
Substrates
Commentary Substrates
Literature (Substrates)
Organism
Products
Commentary (Products)
Literature (Products)
Organism (Products)
Reversibility
7.2.1.1
NADH + H+ + ubiquinone + n Na+/in
-
713414
Vibrio cholerae
NAD+ + ubiquinol + n Na+/out
-
-
-
?
General Information
EC Number
General Information
Commentary
Organism
7.2.1.1
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
General Information (protein specific)
EC Number
General Information
Commentary
Organism
7.2.1.1
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