Cloned (Comment) | Organism |
---|---|
three expression systems are designed, TtHCS without tag, with a C-terminal His6 tag and with a N-terminal His8 tag, the vectors pBluescript II SK+ and pET26b+ are used for expression in Escherichia coli cells | Thermus thermophilus |
Crystallization (Comment) | Organism |
---|---|
the crystal structures of homocitrate synthase complexed with 2-oxoglutarate, (R)-2-hydroxybutane-1,2,4-tricarboxylate, or lysine are determined | Thermus thermophilus |
Protein Variants | Comment | Organism |
---|---|---|
H72L | replacement of His72 by leucine makes HCS resistant to lysine inhibition, demonstrating the regulatory role of this conserved residue | Thermus thermophilus |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
lysine | regulated via feedback inhibition by the endproduct | Thermus thermophilus |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.0054 | - |
2-oxoglutarate | wild-type enzyme, N-terminal His8 tag | Thermus thermophilus | |
0.033 | - |
acetyl-CoA | wild-type enzyme, N-terminal His8 tag | Thermus thermophilus | |
0.037 | - |
acetyl-CoA | H72L mutant, N-terminal His8 tag | Thermus thermophilus | |
0.174 | - |
2-oxoglutarate | H72L mutant, N-terminal His8 tag | Thermus thermophilus |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
acetyl-CoA + H2O + 2-oxoglutarate | Thermus thermophilus | - |
(R)-2-hydroxybutane-1,2,4-tricarboxylate + CoA | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Thermus thermophilus | - |
- |
- |
Purification (Comment) | Organism |
---|---|
a Ni2+-nitrilotriacetic acid column, a gel filtration column, a HiLoad 26/60 phenyl-Sepharose column and a Resource Q anion exchange column are used | Thermus thermophilus |
Specific Activity Minimum [µmol/min/mg] | Specific Activity Maximum [µmol/min/mg] | Comment | Organism |
---|---|---|---|
- |
- |
no activity without additive | Thermus thermophilus |
0.0003 | - |
additive CuCl2 | Thermus thermophilus |
0.0008 | - |
additive FeSO4 | Thermus thermophilus |
0.0013 | - |
additive ZnSO4 | Thermus thermophilus |
0.0036 | - |
additive NiCl2 | Thermus thermophilus |
0.0075 | - |
additive CaCl2 | Thermus thermophilus |
0.0333 | - |
additive CoCl2 | Thermus thermophilus |
0.0392 | - |
additive MnCl2 | Thermus thermophilus |
0.0415 | - |
additive MgSO4 | Thermus thermophilus |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
acetyl-CoA + H2O + 2-oxoglutarate | - |
Thermus thermophilus | (R)-2-hydroxybutane-1,2,4-tricarboxylate + CoA | - |
? |
Synonyms | Comment | Organism |
---|---|---|
HCS | - |
Thermus thermophilus |
homocitrate synthase | - |
Thermus thermophilus |
TtHCS | - |
Thermus thermophilus |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
50 | - |
activity assay | Thermus thermophilus |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.182 | - |
2-oxoglutarate | wild-type enzyme, N-terminal His8 tag | Thermus thermophilus | |
0.248 | - |
2-oxoglutarate | H72L mutant, N-terminal His8 tag | Thermus thermophilus | |
0.517 | - |
acetyl-CoA | H72L mutant, N-terminal His8 tag | Thermus thermophilus | |
0.683 | - |
acetyl-CoA | wild-type enzyme, N-terminal His8 tag | Thermus thermophilus |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
7.5 | - |
activity assay | Thermus thermophilus |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
acetyl-CoA | - |
Thermus thermophilus |
Ki Value [mM] | Ki Value maximum [mM] | Inhibitor | Comment | Organism | Structure |
---|---|---|---|---|---|
0.0707 | - |
lysine | wild-type enzyme, N-terminal His8 tag | Thermus thermophilus | |
2 | - |
lysine | H72L mutant, N-terminal His8 tag, larger than 2 | Thermus thermophilus |
General Information | Comment | Organism |
---|---|---|
metabolism | reaction is the first step in the lysine biosynthetic pathway through alpha-aminoadipate | Thermus thermophilus |