Protein Variants | Comment | Organism |
---|---|---|
V-HisRS-R259K | mutants: V-HisRS-R259K, V-HisRS-R259Q, des(A2-G10)-HisRS, des(A2-Q6)-HisRS, V-His-RS with N-terminal addition of valine, and M-HisRS with N-terminal addition of methionine. N-terminal addition of either methionine or valine, or the deletion of 6 amino terminal amino acids deceases the specific aminoacylation activity 2fold to 7fold. Further N-terminal deletions of 10 or 17 amino acids causes 100fold reduced aminoacylation and 10fold reduced ATP-diphosphate exchange. Removal of 18 or more amino acids from the N-terminus results in an inactive enzyme mutants. The two point mutations R259Q and R259K, show blocked histidyl-tRNA synthetase activity without affecting histidine or ATP binding | Escherichia coli |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.008 | - |
His | HisRS, aminoacylation | Escherichia coli | |
0.011 | - |
His | mutant enzyme form M-HisRS, aminoacylation | Escherichia coli | |
0.017 | - |
His | mutant enzyme form V-HisRS, mutant enzyme form V-His-RS-R259K, aminoacylation | Escherichia coli | |
0.02 | - |
His | mutant enzyme form des(A2-Q6)-HisRS, aminoacylation | Escherichia coli | |
0.06 | - |
His | mutant enzyme form des(A2-G10)-HisRS, aminoacylation | Escherichia coli | |
0.22 | - |
ATP | mutant enzyme form des(A2-Q6), ATP-diphosphate exchange | Escherichia coli | |
0.3 | - |
ATP | mutant enzyme form V-HisRS-R259K, ATP-diphosphate exchange | Escherichia coli | |
0.33 | - |
ATP | mutant enzyme form V-HisRS-R259Q, ATP-diphosphate exchange | Escherichia coli | |
0.35 | - |
ATP | mutant enzyme form V-HisRS, ATP-diphosphate exchange | Escherichia coli | |
0.39 | - |
ATP | mutant enzyme form M-HisRS, ATP-diphosphate exchange | Escherichia coli | |
0.56 | - |
ATP | HisRS, ATP-diphosphate exchange | Escherichia coli | |
0.655 | - |
ATP | mutant enzyme form des(A2-G10)HisRS, ATP-diphosphate exchange | Escherichia coli |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Escherichia coli | - |
wild-type and mutants, V-HisRS-R259K, V-HisRS-R259Q, des(A2-G10)-HisRS, des(A2-Q6)-HisRS, V-His-RS (N-terminal addition of valine), and M-HisRS (N-terminal addition of methionine) | - |
Purification (Comment) | Organism |
---|---|
- |
Escherichia coli |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
ATP + L-histidine + tRNAHis | - |
Escherichia coli | AMP + diphosphate + L-histidyl-tRNAHis | - |
? | |
additional information | ATP-diphosphate exchange | Escherichia coli | ? | - |
? |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.1 | - |
His | mutant enzyme form V-HisRS-R259K, aminoacylation | Escherichia coli | |
0.2 | - |
ATP | mutant enzyme form des(A2-G10)-HisRS, ATP-diphosphate exchange | Escherichia coli | |
0.4 | - |
ATP | mutant enzyme form V-HisRS-R259Q, ATP-diphosphate exchange | Escherichia coli | |
1 | - |
His | mutant enzyme form des(A2-G10)-HisRS, aminoacylation | Escherichia coli | |
6 | - |
His | enzyme form with N-terminal addition of methionine M-HisRS, enzyme form with N-terminal addition of valineV-HisRS, aminoacylation | Escherichia coli | |
7 | - |
His | wild-type HisRS, aminoacylation | Escherichia coli | |
8 | - |
ATP | enzyme form with N-terminal addition of valine V-HisRS, mutant enzyme form des(A2-Q6)-HisRS, ATP-diphosphate exchange | Escherichia coli | |
9 | - |
His | mutant enzyme form des(A2-Q6)-HisRS, aminoacylation, ATP, and mutant enzyme form with N-terminal addition of methionine M-HisRS, ATP-diphosphate exchange | Escherichia coli | |
34 | - |
ATP | HisRS, ATP-diphosphate exchange | Escherichia coli |