Cloned (Comment) | Organism |
---|---|
gene valS, expression of His-tagged wild-type and mutant enzymes in strain JM101Tr | Escherichia coli |
Protein Variants | Comment | Organism |
---|---|---|
K277A | site-directed mutagenesis, mutant exhibits a reduced posttransfer editing activity compared to the wild-type, also the specificiy of the editing reaction is modulated, the mutant hydrolyzes the correctly formed Val-tRNAVal, increased sensitivity to Mg2+, high concentrations inactivate | Escherichia coli |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
additional information | incorporation of 2.1 mol L-valine per mol of enzyme leads to inactivation | Escherichia coli |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.00008 | - |
tRNAVal | aminoacylation reaction with L-valine, wild-type enzyme, pH 7.5, 25°C | Escherichia coli | |
0.0001 | - |
tRNAVal | aminoacylation reaction with L-valine, His-tagged wild-type enzyme, pH 7.5, 25°C | Escherichia coli | |
0.0001 | - |
tRNAVal | aminoacylation reaction with L-valine, K277A mutant enzyme, pH 7.5, 25°C | Escherichia coli | |
0.00026 | - |
tRNAVal | aminoacylation reaction with L-valine, His-tagged K277A mutant enzyme, pH 7.5, 25°C | Escherichia coli | |
0.0019 | - |
L-valine | aminoacylation reaction, His-tagged K277A mutant enzyme, pH 7.5, 25°C | Escherichia coli | |
0.047 | - |
L-valine | aminoacylation reaction, His-tagged wild-type enzyme, pH 7.5, 25°C | Escherichia coli | |
0.062 | - |
L-valine | ATP-diphosphate exchange reaction, native wild-type enzyme, pH 7.5, 25°C | Escherichia coli | |
0.07 | - |
L-valine | ATP-diphosphate exchange reaction, His-tagged wild-type enzyme, pH 7.5, 25°C | Escherichia coli | |
0.072 | - |
L-valine | ATP-diphosphate exchange reaction, His-tagged K277A mutant enzyme, pH 7.5, 25°C | Escherichia coli | |
0.11 | - |
ATP | ATP-diphosphate exchange reaction, His-tagged wild-type and mutant enzymes, pH 7.5, 25°C | Escherichia coli | |
0.3 | - |
L-threonine | ATP-diphosphate exchange reaction, native wild-type enzyme, pH 7.5, 25°C | Escherichia coli |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Mg2+ | required, high concentrations partly inactivate the mutant 277A | Escherichia coli |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
ATP + L-valine + tRNAVal | Escherichia coli | - |
AMP + diphosphate + L-valyl-tRNAVal | - |
ir |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Escherichia coli | - |
- |
- |
Purification (Comment) | Organism |
---|---|
recombinantly expressed His-tagged wild-type and mutant enzymes | Escherichia coli |
Reaction | Comment | Organism | Reaction ID |
---|---|---|---|
ATP + L-valine + tRNAVal = AMP + diphosphate + L-valyl-tRNAVal | Lys593 and Lys554 are in the active site binding valine or threonine, part of the 554KMSKS558 consensus sequence, mechanism, determination of diverse amino acid residues of the enzyme molecule involved in substrate binding, Lys277 plays a crucial role in the fidelity of tRNA aminoacylation by the enzyme, nucleophilic attack of misacylated tRNA in the diting site of the enzyme | Escherichia coli |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
ATP + L-threonine + tRNAVal | noncognate isosteric substrate, low activity, posttransfer editing occurs | Escherichia coli | AMP + diphosphate + L-threonyl-tRNAVal | - |
ir | |
ATP + L-valine + tRNAVal | - |
Escherichia coli | AMP + diphosphate + L-valyl-tRNAVal | - |
ir | |
ATP + L-valine + tRNAVal | two-step reaction, covalent valylation of the enzyme | Escherichia coli | AMP + diphosphate + L-valyl-tRNAVal | - |
ir | |
additional information | the enzyme also performs the ATP-diphosphate exchange reaction, labeling of the enzyme by methionyladenylate, determination of lysine residues involved in binding | Escherichia coli | ? | - |
? |
Synonyms | Comment | Organism |
---|---|---|
G7a | - |
Escherichia coli |
Synthetase, valyl-transfer ribonucleate | - |
Escherichia coli |
Valine transfer ribonucleate ligase | - |
Escherichia coli |
Valine translase | - |
Escherichia coli |
Valine--tRNA ligase | - |
Escherichia coli |
ValRS | - |
Escherichia coli |
Valyl transfer ribonucleic acid synthetase | - |
Escherichia coli |
Valyl-transfer ribonucleate synthetase | - |
Escherichia coli |
Valyl-transfer RNA synthetase | - |
Escherichia coli |
Valyl-tRNA ligase | - |
Escherichia coli |
Valyl-tRNA synthetase | - |
Escherichia coli |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
25 | - |
assay at | Escherichia coli |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
additional information | - |
additional information | rate of hydrolysis of Thr-tRNAVal and Val-tRNAVal by wild-type and mutant enzyme, incorporation of amino acids valine and threonine into the enzyme | Escherichia coli | |
0.064 | - |
L-valine | aminoacylation reaction, His-tagged K277A mutant enzyme, pH 7.5, 25°C | Escherichia coli | |
1.5 | - |
tRNAVal | aminoacylation reaction with L-valine, K277A mutant enzyme, pH 7.5, 25°C | Escherichia coli | |
1.5 | - |
L-valine | aminoacylation reaction, His-tagged wild-type enzyme, pH 7.5, 25°C | Escherichia coli | |
1.7 | - |
tRNAVal | aminoacylation reaction with L-valine, wild-type enzyme, pH 7.5, 25°C | Escherichia coli | |
50 | - |
ATP | ATP-diphosphate exchange reaction, His-tagged wild-type enzyme, pH 7.5, 25°C | Escherichia coli | |
50 | - |
tRNAVal | ATP-diphosphate exchange reaction, K277A mutant enzyme, pH 7.5, 25°C | Escherichia coli | |
51 | - |
tRNAVal | ATP-diphosphate exchange reaction, wild-type enzyme, pH 7.5, 25°C | Escherichia coli | |
57 | - |
ATP | ATP-diphosphate exchange reaction, His-tagged K277A mutant enzyme, pH 7.5, 25°C | Escherichia coli |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
7.5 | - |
assay at | Escherichia coli |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
ATP | - |
Escherichia coli |