Protein Variants | Comment | Organism |
---|---|---|
A328V | site-directed mutagenesis of the conserved residue, the site-specific dihydrolipoamide dehydrogenase mutant shows a switched kinetic mechanism, it shows a random sequential kinetic mechanism with an interaction factor (alpha) of 8.5. The mutation deteriorates substantially the catalytic power of human E3 enzyme increasing the binding affinity for NAD+ and dihydrolipoamide . The mutation triggers this potential intrinsic property of the enzyme causing the kinetic mechanism of the mutant to switch from a ping-pong mechanism to a random sequential mechanism | Homo sapiens |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
additional information | - |
additional information | kinetic analysis and mechanisms of wild-type and mutant enzymes, overview | Homo sapiens | |
0.024 | - |
NAD+ | enzyme mutant, pH 8.0, 37°C | Homo sapiens | |
0.027 | - |
dihydrolipoamide | enzyme mutant, pH 8.0, 37°C | Homo sapiens | |
0.19 | - |
NAD+ | wild-type enzyme, pH 8.0, 37°C | Homo sapiens | |
0.63 | - |
dihydrolipoamide | wild-type enzyme, pH 8.0, 37°C | Homo sapiens |
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 | - |
- |
Reaction | Comment | Organism | Reaction ID |
---|---|---|---|
protein N6-(dihydrolipoyl)lysine + NAD+ = protein N6-(lipoyl)lysine + NADH + H+ | kinetic mechanism of human E3 enzyme is a ping-pong mechanism. In human E3, dihydrolipoamide binds to the si-face of FAD, whereas NAD+ binds to the re-face. These two spatially separate substrate binding sites can allow the enzyme to form a ternary complex with two substrates, which is an essential feature of the sequential mechanism | 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 |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
8 | - |
assay at | Homo sapiens |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
FAD | - |
Homo sapiens | |
NAD+ | - |
Homo sapiens | |
NADH | - |
Homo sapiens |
General Information | Comment | Organism |
---|---|---|
evolution | E3 belongs to the pyridine nucleotide-disulfide oxidoreductase family along with glutathione reductase (GR), thioredoxin reductase, mercuric reductase and trypanothione reductase | Homo sapiens |
additional information | residue Ala328 is absolutely conserved, suggesting that it might be important for the structure and function of human E3. Ala328 is a component of alpha-helix 8 and is located near the presumed dihydrolipoamide binding channel. Ala328 is also located close to the active disulfide center between Cys45 and Cys50 | Homo sapiens |
physiological function | E3 catalyzes the reoxidation of the dihydrolipoyl prosthetic group attached to the lysyl residue(s) of the acyltransferase components of these dehydrogenase complexes | Homo sapiens |