Cloned (Comment) | Organism |
---|---|
gene dld, recombinant expression of His-tagged wild-type and mutant enzymes in Escherichia coli strain XL-1 Blue | Homo sapiens |
Protein Variants | Comment | Organism |
---|---|---|
C50A | site-directed mutagenesis, catalytic efficiency of mutant C50A toward NAD+ decreases 5317fold compared to the wild-type enzyme, the mutation destroys the active disulfide center between Cys45 and Cys50, which restricts the freedom of Cys50 | Homo sapiens |
C50T | site-directed mutagenesis, catalytic efficiency of mutant C50A toward NAD+ decreases 2057fold compared to the wild-type enzyme, the mutation destroys the active disulfide center between Cys45 and Cys50, which restricts the freedom of Cys50 | Homo sapiens |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.16 | - |
dihydrolipoamide | enzyme mutant C50T, pH 8.0, 37°C | Homo sapiens | |
0.19 | - |
NAD+ | wild-type enzyme, pH 8.0, 37°C | Homo sapiens | |
0.2 | - |
NAD+ | enzyme mutant C50T, pH 8.0, 37°C | Homo sapiens | |
0.22 | - |
dihydrolipoamide | enzyme mutant C50A, pH 8.0, 37°C | Homo sapiens | |
0.47 | - |
NAD+ | enzyme mutant C50A, pH 8.0, 37°C | Homo sapiens | |
0.64 | - |
dihydrolipoamide | wild-type enzyme, pH 8.0, 37°C | Homo sapiens |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
mitochondrion | - |
Homo sapiens | 5739 | - |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
dihydrolipoamide + NAD+ | Homo sapiens | - |
lipoamide + NADH + H+ | - |
r |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Homo sapiens | P09622 | - |
- |
Purification (Comment) | Organism |
---|---|
recombinant His-tagged wild-type and mutant enzymes from Escherichia coli strain XL-1 Blue by nickel affinity chromatography and dialysis | Homo sapiens |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
dihydrolipoamide + NAD+ | - |
Homo sapiens | lipoamide + NADH + H+ | - |
r |
Subunits | Comment | Organism |
---|---|---|
homodimer | - |
Homo sapiens |
Synonyms | Comment | Organism |
---|---|---|
dihydrolipoamide dehydrogenase | - |
Homo sapiens |
dihydrolipoamide:NAD+ oxidoreductase | - |
Homo sapiens |
E3 | - |
Homo sapiens |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
37 | - |
assay at | Homo sapiens |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.42 | - |
NAD+ | enzyme mutant C50A, pH 8.0, 37°C | Homo sapiens | |
0.42 | - |
dihydrolipoamide | enzyme mutant C50A, pH 8.0, 37°C | Homo sapiens | |
0.46 | - |
NAD+ | enzyme mutant C50T, pH 8.0, 37°C | Homo sapiens | |
0.46 | - |
dihydrolipoamide | enzyme mutant C50T, pH 8.0, 37°C | Homo sapiens | |
899 | - |
NAD+ | wild-type enzyme, pH 8.0, 37°C | Homo sapiens | |
899 | - |
dihydrolipoamide | wild-type enzyme, pH 8.0, 37°C | Homo sapiens |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
8 | - |
assay at | Homo sapiens |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
FAD | one FAD as a prosthetic group at each subunit | Homo sapiens | |
NAD+ | - |
Homo sapiens | |
NADH | - |
Homo sapiens |
General Information | Comment | Organism |
---|---|---|
evolution | residue Cys50 is absolutely conserved, Cys50 is a component of the very long a-helix structure 2, which is composed of 25 amino acids. Residue Cys50 forms an active disulfide center with Cys45 | Homo sapiens |
malfunction | as a common component in three 2-oxo acid dehydrogenase, a decrease in E3 activity affects the activities of all three complexes, which leads to increased urinary excretion of 2-oxo acids, elevated blood lactate, pyruvate, and branched chain amino acids. Patients with an E3 deficiency normally die young because an E3 deficiency is a critical genetic defect affecting the central nervous system. A deficiency in E3 results in Leigh syndrome with recurrent episodes of hypoglycemia and ataxia, permanent lactic acidaemia, and mental retardation. A C45A mutation results in a large decrease in human E3 activity and changes in the spectroscopic properties of human E3 | Homo sapiens |
additional information | location of residue Cys50 in human E3 enzyme, structure comparisons with E3 enzymes from other species | Homo sapiens |
physiological function | E3 is an essential component in pyruvate, 2-oxoglutarate and branched-chain 2-oxo acid dehydrogenase complexes. E3 catalyzes the reoxidation of a dihydrolipoyl prosthetic group attached to the lysyl residue(s) of the acyltransferase components of the three 2-oxo acid dehydrogenase complexes | Homo sapiens |
kcat/KM Value [1/mMs-1] | kcat/KM Value Maximum [1/mMs-1] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.89 | - |
NAD+ | enzyme mutant C50A, pH 8.0, 37°C | Homo sapiens | |
2.3 | - |
NAD+ | enzyme mutant C50T, pH 8.0, 37°C | Homo sapiens | |
4731.6 | - |
NAD+ | wild-type enzyme, pH 8.0, 37°C | Homo sapiens |