BRENDA - Enzyme Database show

Characterization of a variant iron protein of nitrogenase that is impaired in its ability to adopt the MgATP-induced conformational change

Bursey, E.H.; Burgess, B.K.; J. Biol. Chem. 273, 16927-16934 (1998)

Data extracted from this reference:

Engineering
EC Number
Amino acid exchange
Commentary
Organism
1.18.6.1
A175G
shows in vivo 55% of enzyme activity compared to wild-type, in vitro 20% activity remaining with purified enzyme, slowlier conformational change upon binding of MgATP, model of steric interactions using x-ray crystal structures
Azotobacter vinelandii
1.18.6.1
A175S
unable to support substrate reduction because of an inability to undergo a required MgATP-induced conformational change
Azotobacter vinelandii
Metals/Ions
EC Number
Metals/Ions
Commentary
Organism
Structure
1.18.6.1
Iron
-
Azotobacter vinelandii
1.18.6.1
Mg2+
Mg2+ required for MgATP complex
Azotobacter vinelandii
1.18.6.1
Molybdenum
-
Azotobacter vinelandii
Natural Substrates/ Products (Substrates)
EC Number
Natural Substrates
Organism
Commentary (Nat. Sub.)
Natural Products
Commentary (Nat. Pro.)
Organism (Nat. Pro.)
Reversibility
1.18.6.1
8 reduced ferredoxin + 8 H+ + N2 + 16 ATP + 16 H2O
Azotobacter vinelandii
-
8 oxidized ferredoxin + H2 + 2 NH3 + 16 ADP + 16 phosphate
-
-
?
Organism
EC Number
Organism
Primary Accession No. (UniProt)
Commentary
Textmining
1.18.6.1
Azotobacter vinelandii
-
nitrogen fixation complex is encoded on nif gene cluster
-
Reaction
EC Number
Reaction
Commentary
Organism
1.18.6.1
8 reduced ferredoxin + 8 H+ + N2 + 16 ATP + 16 H2O = 8 oxidized ferredoxin + H2 + 2 NH3 + 16 ADP + 16 phosphate
enzyme is composed of 2 metalloproteins: component I MoFe protein and component II Fe protein
Azotobacter vinelandii
Specific Activity [micromol/min/mg]
EC Number
Specific Activity Minimum [Ámol/min/mg]
Specific Activity Maximum [Ámol/min/mg]
Commentary
Organism
1.18.6.1
additional information
-
assay in anaerobic atmosphere required
Azotobacter vinelandii
1.18.6.1
0.27
-
mutant A175G, purified enzyme, substrate C2H2
Azotobacter vinelandii
1.18.6.1
1.52
-
wild-type, purified enzyme, substrate C2H2
Azotobacter vinelandii
Substrates and Products (Substrate)
EC Number
Substrates
Commentary Substrates
Literature (Substrates)
Organism
Products
Commentary (Products)
Literature (Products)
Organism (Products)
Reversibility
1.18.6.1
2 reduced ferredoxin + 2 H+ + acetylene + 2 ATP + 2 H2O
-
440182
Azotobacter vinelandii
2 oxidized ferredoxin + ethylene + 2 ADP + 2 phosphate
-
440182
Azotobacter vinelandii
?
1.18.6.1
8 reduced ferredoxin + 8 H+ + N2 + 16 ATP + 16 H2O
-
440182
Azotobacter vinelandii
8 oxidized ferredoxin + H2 + 2 NH3 + 16 ADP + 16 phosphate
-
-
-
?
1.18.6.1
8 reduced ferredoxin + 8 H+ + N2 + 16 ATP + 16 H2O
MgATP-dependent
440182
Azotobacter vinelandii
8 oxidized ferredoxin + H2 + 2 NH3 + 16 ADP + 16 phosphate
-
440182
Azotobacter vinelandii
?
Temperature Optimum [░C]
EC Number
Temperature Optimum [░C]
Temperature Optimum Maximum [░C]
Commentary
Organism
1.18.6.1
30
-
assay at
Azotobacter vinelandii
pH Optimum
EC Number
pH Optimum Minimum
pH Optimum Maximum
Commentary
Organism
1.18.6.1
7.4
-
assay at
Azotobacter vinelandii
Engineering (protein specific)
EC Number
Amino acid exchange
Commentary
Organism
1.18.6.1
A175G
shows in vivo 55% of enzyme activity compared to wild-type, in vitro 20% activity remaining with purified enzyme, slowlier conformational change upon binding of MgATP, model of steric interactions using x-ray crystal structures
Azotobacter vinelandii
1.18.6.1
A175S
unable to support substrate reduction because of an inability to undergo a required MgATP-induced conformational change
Azotobacter vinelandii
Metals/Ions (protein specific)
EC Number
Metals/Ions
Commentary
Organism
Structure
1.18.6.1
Iron
-
Azotobacter vinelandii
1.18.6.1
Mg2+
Mg2+ required for MgATP complex
Azotobacter vinelandii
1.18.6.1
Molybdenum
-
Azotobacter vinelandii
Natural Substrates/ Products (Substrates) (protein specific)
EC Number
Natural Substrates
Organism
Commentary (Nat. Sub.)
Natural Products
Commentary (Nat. Pro.)
Organism (Nat. Pro.)
Reversibility
1.18.6.1
8 reduced ferredoxin + 8 H+ + N2 + 16 ATP + 16 H2O
Azotobacter vinelandii
-
8 oxidized ferredoxin + H2 + 2 NH3 + 16 ADP + 16 phosphate
-
-
?
Specific Activity [micromol/min/mg] (protein specific)
EC Number
Specific Activity Minimum [Ámol/min/mg]
Specific Activity Maximum [Ámol/min/mg]
Commentary
Organism
1.18.6.1
additional information
-
assay in anaerobic atmosphere required
Azotobacter vinelandii
1.18.6.1
0.27
-
mutant A175G, purified enzyme, substrate C2H2
Azotobacter vinelandii
1.18.6.1
1.52
-
wild-type, purified enzyme, substrate C2H2
Azotobacter vinelandii
Substrates and Products (Substrate) (protein specific)
EC Number
Substrates
Commentary Substrates
Literature (Substrates)
Organism
Products
Commentary (Products)
Literature (Products)
Organism (Products)
Reversibility
1.18.6.1
2 reduced ferredoxin + 2 H+ + acetylene + 2 ATP + 2 H2O
-
440182
Azotobacter vinelandii
2 oxidized ferredoxin + ethylene + 2 ADP + 2 phosphate
-
440182
Azotobacter vinelandii
?
1.18.6.1
8 reduced ferredoxin + 8 H+ + N2 + 16 ATP + 16 H2O
-
440182
Azotobacter vinelandii
8 oxidized ferredoxin + H2 + 2 NH3 + 16 ADP + 16 phosphate
-
-
-
?
1.18.6.1
8 reduced ferredoxin + 8 H+ + N2 + 16 ATP + 16 H2O
MgATP-dependent
440182
Azotobacter vinelandii
8 oxidized ferredoxin + H2 + 2 NH3 + 16 ADP + 16 phosphate
-
440182
Azotobacter vinelandii
?
Temperature Optimum [░C] (protein specific)
EC Number
Temperature Optimum [░C]
Temperature Optimum Maximum [░C]
Commentary
Organism
1.18.6.1
30
-
assay at
Azotobacter vinelandii
pH Optimum (protein specific)
EC Number
pH Optimum Minimum
pH Optimum Maximum
Commentary
Organism
1.18.6.1
7.4
-
assay at
Azotobacter vinelandii