Protein Variants | Comment | Organism |
---|---|---|
W139F/E360W | exhibits catalytic activity comparable to that of the native enzyme and is effectively inhibited by L-serine. The only fluorescence signal of the mutant is due to the single tryptophan at position 360. Pre-steady state analysis of binding of inhibitor serine shows that each serine binding interface produces an integrated fluorescent signal | Escherichia coli |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
L-serine | physiological inhibitor, exerts its effect on at least two steps in the kinetic mechanism. There is a small but significant effect on the dissociation constant of NADH, increasing the Kd to 5 and 23 microM from 0.6 and 9 microM, respectively, for the two sets of sites in the enzyme. After the second substrate is added, serine reduces the amplitude of the signal without a significant effect on the observed rate constants for binding. The serine concentration that reduces the amplitude by 50% is equal to the K0.5 for serine inhibition. Serine binding eliminates a conformational change subsequent to substrate binding by formation of a dead-end quaternary complex consisting of enzyme, coenzyme, substrate, and effector. The rate data conform to a model in which serine can bind to two forms of the enzyme with different affinities | Escherichia coli |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Escherichia coli | P0A9T0 | - |
- |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
2-oxoglutarate + NADH + H+ | - |
Escherichia coli | 2-hydroxyglutarate + NAD+ | - |
? |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
NADH | - |
Escherichia coli |