BRENDA - Enzyme Database

Each conserved active site tyr in the three subunits of human isocitrate dehydrogenase has a different function

Dange, M.; Colman, R.F.; J. Biol. Chem. 285, 20520-20525 (2010)

Data extracted from this reference:

Activating Compound
EC Number
Activating Compound
Commentary
Organism
Structure
1.1.1.41
ADP
allosteric activation by ADP involving residue betaY126. In the presence of 1 mM ADP, the Km,isocitrate is reduced almost equally in the wild-type, 3.6fold, and the alphaY126E mutant, 4.3fold
Homo sapiens
Cloned(Commentary)
EC Number
Commentary
Organism
1.1.1.41
expression of wild-type and mutant NAD-IDHs in Escherichia coli
Homo sapiens
Engineering
EC Number
Amino acid exchange
Commentary
Organism
1.1.1.41
alphaY126E
site-directed mutagenesis of subunit alpha, almost inactive mutant, shows low activity at pH 6.1 instead of pH 7.2, Km,Mn2+ is 30fold higher in the alphaY126E mutant as compared with the wild-type. Km,NAD+ for the alphaY126E mutant is 29fold higher than that of the wild-type. The Vmax of the wild-type at pH 6.1 is 0.0144 mmol/min/mg, whereas that for the alphaY126E mutant is only 0.00103 mmol/min/mg, suggesting a critical role for the residue in enzyme activity
Homo sapiens
1.1.1.41
alphaY126F
site-directed mutagenesis of subunit alpha, inactive mutant
Homo sapiens
1.1.1.41
alphaY126S
site-directed mutagenesis of subunit alpha, inactive mutant
Homo sapiens
1.1.1.41
betaY137E
site-directed mutagenesis of subunit beta, the mutant shows reduced activity compared to the wild-type enzyme
Homo sapiens
1.1.1.41
betaY137F
site-directed mutagenesis of subunit beta, the mutant shows reduced activity compared to the wild-type enzyme
Homo sapiens
1.1.1.41
betaY137S
site-directed mutagenesis of subunit beta, the mutant shows reduced activity compared to the wild-type enzyme
Homo sapiens
1.1.1.41
gammaY135F
site-directed mutagenesis of subunit gamma, inactive mutant
Homo sapiens
KM Value [mM]
EC Number
KM Value [mM]
KM Value Maximum [mM]
Substrate
Commentary
Organism
Structure
1.1.1.41
0.06
-
NAD+
pH 7.2, 25°C, recombinant wild-type enzyme
Homo sapiens
1.1.1.41
0.09
-
isocitrate
pH 7.2, 25°C, recombinant mutant betaY137E, in presence of 1 mM ADP
Homo sapiens
1.1.1.41
0.09
-
NAD+
pH 7.2, 25°C, recombinant mutant betaY137E
Homo sapiens
1.1.1.41
0.12
-
NAD+
pH 7.2, 25°C, recombinant mutant betaY137F
Homo sapiens
1.1.1.41
0.28
-
isocitrate
pH 7.2, 25°C, recombinant mutant betaY137F, in presence of 1 mM ADP
Homo sapiens
1.1.1.41
0.5
-
isocitrate
pH 7.2, 25°C, recombinant wild-type enzyme, in presence of 1 mM ADP
Homo sapiens
1.1.1.41
0.63
-
NAD+
pH 7.2, 25°C, recombinant mutant betaY137S
Homo sapiens
1.1.1.41
0.92
-
isocitrate
pH 7.2, 25°C, recombinant mutant betaY137S, in presence of 1 mM ADP
Homo sapiens
1.1.1.41
1.2
-
isocitrate
pH 7.2, 25°C, recombinant mutant betaY137S
Homo sapiens
1.1.1.41
1.8
-
isocitrate
pH 7.2, 25°C, recombinant mutant betaY137F
Homo sapiens
1.1.1.41
2
-
isocitrate
pH 7.2, 25°C, recombinant wild-type enzyme
Homo sapiens
1.1.1.41
3.4
-
isocitrate
pH 7.2, 25°C, recombinant mutant betaY137E
Homo sapiens
Localization
EC Number
Localization
Commentary
Organism
GeneOntology No.
Textmining
1.1.1.41
mitochondrion
-
Homo sapiens
5739
-
Metals/Ions
EC Number
Metals/Ions
Commentary
Organism
Structure
1.1.1.41
Mn2+
activates, Km values for wild-type and betaY137 mutants are 0.11-0.18 mM
Homo sapiens
Natural Substrates/ Products (Substrates)
EC Number
Natural Substrates
Organism
Commentary (Nat. Sub.)
Natural Products
Commentary (Nat. Pro.)
Organism (Nat. Pro.)
Reversibility
1.1.1.41
isocitrate + NAD+
Homo sapiens
-
2-oxoglutarate + NADH + H+ + CO2
-
-
?
Organism
EC Number
Organism
Primary Accession No. (UniProt)
Commentary
Textmining
1.1.1.41
Homo sapiens
-
-
-
Purification (Commentary)
EC Number
Commentary
Organism
1.1.1.41
recombinant wild-type and mutant NAD-IDHs from Escherichia coli by ammonium sulfate fractionation, anion exchange chromatography, ultrafiltration, and gel filtration
Homo sapiens
Substrates and Products (Substrate)
EC Number
Substrates
Commentary Substrates
Literature (Substrates)
Organism
Products
Commentary (Products)
Literature (Products)
Organism (Products)
Reversibility
1.1.1.41
isocitrate + NAD+
-
712440
Homo sapiens
2-oxoglutarate + NADH + H+ + CO2
-
-
-
?
1.1.1.41
isocitrate + NAD+
residue Y137 of subunit beta is involved in NAD+ binding and allosteric activation by ADP, residue Y126 of subunit alpha is required for catalytic activity and likely acts as a general acid in the reaction, gammaY135 is also required for catalytic activity and may be involved in proper folding of the enzyme. The corresponding tyrosines in the three dissimilar subunits of NAD-IDH thus have distinctive functions
712440
Homo sapiens
2-oxoglutarate + NADH + H+ + CO2
-
-
-
?
Subunits
EC Number
Subunits
Commentary
Organism
1.1.1.41
heterotetramer
determination of secondary structure by circular dichroism, subunit molar ratio of wild-type and mutant NAD-IDHs, overview
Homo sapiens
Temperature Optimum [°C]
EC Number
Temperature Optimum [°C]
Temperature Optimum Maximum [°C]
Commentary
Organism
1.1.1.41
25
-
assay at
Homo sapiens
pH Optimum
EC Number
pH Optimum Minimum
pH Optimum Maximum
Commentary
Organism
1.1.1.41
7.2
-
assay at
Homo sapiens
Cofactor
EC Number
Cofactor
Commentary
Organism
Structure
1.1.1.41
NAD+
-
Homo sapiens
Activating Compound (protein specific)
EC Number
Activating Compound
Commentary
Organism
Structure
1.1.1.41
ADP
allosteric activation by ADP involving residue betaY126. In the presence of 1 mM ADP, the Km,isocitrate is reduced almost equally in the wild-type, 3.6fold, and the alphaY126E mutant, 4.3fold
Homo sapiens
Cloned(Commentary) (protein specific)
EC Number
Commentary
Organism
1.1.1.41
expression of wild-type and mutant NAD-IDHs in Escherichia coli
Homo sapiens
Cofactor (protein specific)
EC Number
Cofactor
Commentary
Organism
Structure
1.1.1.41
NAD+
-
Homo sapiens
Engineering (protein specific)
EC Number
Amino acid exchange
Commentary
Organism
1.1.1.41
alphaY126E
site-directed mutagenesis of subunit alpha, almost inactive mutant, shows low activity at pH 6.1 instead of pH 7.2, Km,Mn2+ is 30fold higher in the alphaY126E mutant as compared with the wild-type. Km,NAD+ for the alphaY126E mutant is 29fold higher than that of the wild-type. The Vmax of the wild-type at pH 6.1 is 0.0144 mmol/min/mg, whereas that for the alphaY126E mutant is only 0.00103 mmol/min/mg, suggesting a critical role for the residue in enzyme activity
Homo sapiens
1.1.1.41
alphaY126F
site-directed mutagenesis of subunit alpha, inactive mutant
Homo sapiens
1.1.1.41
alphaY126S
site-directed mutagenesis of subunit alpha, inactive mutant
Homo sapiens
1.1.1.41
betaY137E
site-directed mutagenesis of subunit beta, the mutant shows reduced activity compared to the wild-type enzyme
Homo sapiens
1.1.1.41
betaY137F
site-directed mutagenesis of subunit beta, the mutant shows reduced activity compared to the wild-type enzyme
Homo sapiens
1.1.1.41
betaY137S
site-directed mutagenesis of subunit beta, the mutant shows reduced activity compared to the wild-type enzyme
Homo sapiens
1.1.1.41
gammaY135F
site-directed mutagenesis of subunit gamma, inactive mutant
Homo sapiens
KM Value [mM] (protein specific)
EC Number
KM Value [mM]
KM Value Maximum [mM]
Substrate
Commentary
Organism
Structure
1.1.1.41
0.06
-
NAD+
pH 7.2, 25°C, recombinant wild-type enzyme
Homo sapiens
1.1.1.41
0.09
-
isocitrate
pH 7.2, 25°C, recombinant mutant betaY137E, in presence of 1 mM ADP
Homo sapiens
1.1.1.41
0.09
-
NAD+
pH 7.2, 25°C, recombinant mutant betaY137E
Homo sapiens
1.1.1.41
0.12
-
NAD+
pH 7.2, 25°C, recombinant mutant betaY137F
Homo sapiens
1.1.1.41
0.28
-
isocitrate
pH 7.2, 25°C, recombinant mutant betaY137F, in presence of 1 mM ADP
Homo sapiens
1.1.1.41
0.5
-
isocitrate
pH 7.2, 25°C, recombinant wild-type enzyme, in presence of 1 mM ADP
Homo sapiens
1.1.1.41
0.63
-
NAD+
pH 7.2, 25°C, recombinant mutant betaY137S
Homo sapiens
1.1.1.41
0.92
-
isocitrate
pH 7.2, 25°C, recombinant mutant betaY137S, in presence of 1 mM ADP
Homo sapiens
1.1.1.41
1.2
-
isocitrate
pH 7.2, 25°C, recombinant mutant betaY137S
Homo sapiens
1.1.1.41
1.8
-
isocitrate
pH 7.2, 25°C, recombinant mutant betaY137F
Homo sapiens
1.1.1.41
2
-
isocitrate
pH 7.2, 25°C, recombinant wild-type enzyme
Homo sapiens
1.1.1.41
3.4
-
isocitrate
pH 7.2, 25°C, recombinant mutant betaY137E
Homo sapiens
Localization (protein specific)
EC Number
Localization
Commentary
Organism
GeneOntology No.
Textmining
1.1.1.41
mitochondrion
-
Homo sapiens
5739
-
Metals/Ions (protein specific)
EC Number
Metals/Ions
Commentary
Organism
Structure
1.1.1.41
Mn2+
activates, Km values for wild-type and betaY137 mutants are 0.11-0.18 mM
Homo sapiens
Natural Substrates/ Products (Substrates) (protein specific)
EC Number
Natural Substrates
Organism
Commentary (Nat. Sub.)
Natural Products
Commentary (Nat. Pro.)
Organism (Nat. Pro.)
Reversibility
1.1.1.41
isocitrate + NAD+
Homo sapiens
-
2-oxoglutarate + NADH + H+ + CO2
-
-
?
Purification (Commentary) (protein specific)
EC Number
Commentary
Organism
1.1.1.41
recombinant wild-type and mutant NAD-IDHs from Escherichia coli by ammonium sulfate fractionation, anion exchange chromatography, ultrafiltration, and gel filtration
Homo sapiens
Substrates and Products (Substrate) (protein specific)
EC Number
Substrates
Commentary Substrates
Literature (Substrates)
Organism
Products
Commentary (Products)
Literature (Products)
Organism (Products)
Reversibility
1.1.1.41
isocitrate + NAD+
-
712440
Homo sapiens
2-oxoglutarate + NADH + H+ + CO2
-
-
-
?
1.1.1.41
isocitrate + NAD+
residue Y137 of subunit beta is involved in NAD+ binding and allosteric activation by ADP, residue Y126 of subunit alpha is required for catalytic activity and likely acts as a general acid in the reaction, gammaY135 is also required for catalytic activity and may be involved in proper folding of the enzyme. The corresponding tyrosines in the three dissimilar subunits of NAD-IDH thus have distinctive functions
712440
Homo sapiens
2-oxoglutarate + NADH + H+ + CO2
-
-
-
?
Subunits (protein specific)
EC Number
Subunits
Commentary
Organism
1.1.1.41
heterotetramer
determination of secondary structure by circular dichroism, subunit molar ratio of wild-type and mutant NAD-IDHs, overview
Homo sapiens
Temperature Optimum [°C] (protein specific)
EC Number
Temperature Optimum [°C]
Temperature Optimum Maximum [°C]
Commentary
Organism
1.1.1.41
25
-
assay at
Homo sapiens
pH Optimum (protein specific)
EC Number
pH Optimum Minimum
pH Optimum Maximum
Commentary
Organism
1.1.1.41
7.2
-
assay at
Homo sapiens