Application | Comment | Organism |
---|---|---|
synthesis | production of L-tryptophan and related amino acids | Escherichia coli |
Crystallization (Comment) | Organism |
---|---|
apo-form of enzyme without bound pyridoxal 5-phosphate but with two bound sulfate ions, hanging drop vapor diffusion method | Escherichia coli |
strong crystal contacts occur on the flat surface of the protein and that the size of crystal contact surface seems to correlate with the diffraction quality of the crystal. The tryptophanase structure, solved in its apo form, does not have covalent PLP bound in the active site, but two sulfate ions. The sulfate ions occupy the phosphoryl-binding site of PLP and the binding site of the alpha-carboxyl of the natural substrate tryptophan. One of the sulfate ions makes extensive interactions with both the transferase and PLP-binding domains of the protein and appears to be responsible for holding the enzyme in its closed conformation | Escherichia coli |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
K+ | stabilizing, cold inactivation occurs more slowly in the presence of K+ | Escherichia coli | |
sulfate | two ions bound two the active site of the enzyme, one of the sulfate ions interacts with both the transferase and PLP-binding domains and appears to be responsible for holding the enzyme in its closed conformation | Escherichia coli |
Molecular Weight [Da] | Molecular Weight Maximum [Da] | Comment | Organism |
---|---|---|---|
52000 | - |
4 * 52000 | Escherichia coli |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
L-Trp + H2O | Escherichia coli | - |
indole + pyruvate + NH4+ | - |
r | |
L-Trp + H2O | Escherichia coli JM109 | - |
indole + pyruvate + NH4+ | - |
r |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Escherichia coli | P0A853 | - |
- |
Escherichia coli JM109 | P0A853 | - |
- |
Purification (Comment) | Organism |
---|---|
no added pyridoxal 5-phosphate during purification procedure resulting in the inactive apo-form of the enzyme | Escherichia coli |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
D-Trp + H2O | in the presence of high concentrations of ammonium phosphate | Escherichia coli | indole + pyruvate + NH4+ | - |
? | |
D-Trp + H2O | in the presence of high concentrations of ammonium phosphate | Escherichia coli JM109 | indole + pyruvate + NH4+ | - |
? | |
L-Trp + H2O | - |
Escherichia coli | indole + pyruvate + NH4+ | - |
r | |
L-Trp + H2O | - |
Escherichia coli JM109 | indole + pyruvate + NH4+ | - |
r |
Subunits | Comment | Organism |
---|---|---|
dimer | inactive, formed upon cold incubation or purification | Escherichia coli |
tetramer | 4 * 52000 | Escherichia coli |
Temperature Stability Minimum [°C] | Temperature Stability Maximum [°C] | Comment | Organism |
---|---|---|---|
additional information | - |
inactivation of the enzyme at low temperatures due to dissociation of the active tetramer into dimers upon cold incubation | Escherichia coli |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
pyridoxal 5'-phosphate | dependent on | Escherichia coli | |
pyridoxal 5'-phosphate | covalent binding required to activate the enzyme | Escherichia coli |
Organism | Comment | pI Value Maximum | pI Value |
---|---|---|---|
Escherichia coli | calculated from the deduced amino acid sequence | - |
6.2 |