Cloned (Comment) | Organism |
---|---|
gene gluQ, recombinant expression of wild-type and mutant enzymes in Escherichia coli strain BL21(DE3) Rosetta II | Escherichia coli |
Protein Variants | Comment | Organism |
---|---|---|
C101S/C103S | site-directed mutagenesis, in the mutant the zinc ion still remains coordinated but the variant becomes structurally labile and acquires aggregation capacity. The extent of aggregation of the protein is significantly decreased in presence of the small substrates and more particularly by adenosine triphosphate. Addition of zinc increases significantly the solubility of the variant. The aminoacylation assay reveals a decrease in activity of the mutant even after addition of zinc as compared to the wild-type, although the secondary structure of the protein is not altered. Unlike wild type Glu-Q-RS, the mutant shows a strong tendency to aggregate in solution at room temperature, addition of a saturating concentration of the small substrate ATP and/or L-Glu decreases the rate of aggregation of C101S/C103S Glu-Q-RS, ATP has the most efficient effect | Escherichia coli |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Mg2+ | required | Escherichia coli | |
Zn2+ | required, tetracoordinated to residues Cys101, Cys103, Cys119 and Tyr115. The zinc ion has a high impact on the enzyme structure and function. Enzyme Glu-Q-RS contain a single zinc-binding site in their putative tRNA acceptor stem-binding domain. Quantification by X-ray fluorescence spectrometry technique. Absence of saturating zinc in solution displays dramatic change in the solubility of the protein | Escherichia coli |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
ATP + L-glutamate + tRNAAsp | Escherichia coli | - |
AMP + diphosphate + L-glutamyl-tRNAAsp | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Escherichia coli | P27305 | - |
- |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
ATP + L-glutamate + tRNAAsp | - |
Escherichia coli | AMP + diphosphate + L-glutamyl-tRNAAsp | - |
? | |
additional information | Glu-Q-RS glutamylates the Q34 residue of the anticodon of tRNAAsp, hence it is a tRNA hypermodifying enzyme | Escherichia coli | ? | - |
? |
Subunits | Comment | Organism |
---|---|---|
More | determination and comparisons of three-dimensional structures of free enzyme Glu-Q-RS and Glu-bound Glu-Q-RS | Escherichia coli |
Synonyms | Comment | Organism |
---|---|---|
Glu-Q-RS | - |
Escherichia coli |
gluQ | - |
Escherichia coli |
glutamyl-queuosine-tRNAAsp synthetase | - |
Escherichia coli |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
37 | - |
assay at | Escherichia coli |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
7.5 | - |
assay at | Escherichia coli |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
ATP | - |
Escherichia coli |
General Information | Comment | Organism |
---|---|---|
evolution | glutamyl-QtRNA Asp synthetase (Glu-Q-RS) from Escherichia coli is a paralogue of glutamyl-tRNA synthetase, GluRS, both containing one zinc ion | Escherichia coli |
malfunction | Absence of saturating zinc in solution displays dramatic change in the solubility of the protein | Escherichia coli |