EC Number   |
Protein Variants |
Reference |
|---|
    6.1.1.17 | H129Q |
mutants encoding GluRS variants altered in the 98C-138C segment. Thermosensitive mutants H129Q, H131Q, H132Q and C138S. Mutants without glutamyl-tRNA synthetase activity: C100S, C125S. In the mutants C98S and H127Q the activity is 10fold lower than in cells overproducing the wild-type enzyme or the variants H129Q, H131Q, H132Q, and C138S |
206 |
| 6.1.1.17 | K236E/E328A |
by mapping crystal contacts of the homologous GluRS from Bacillus thailandensis, PDB ID 4g6z, onto the Escherichia coli GluRS sequence, two surface residues are identified that might be hindering crystallization attempts. Accordingly, these two residues are mutated and crystallization of the double mutant is attempted |
743955 |
| 6.1.1.17 | more |
construction and expression in Escherichia coli of mutant forms of Escherichia coli tRNAGln2 and tRNAGln1 and of Bacillus subtilis tRNAGln |
492290 |
| 6.1.1.17 | more |
construction and overexpression of tRNAGlu variants, the enzyme shows altered activity with the tRNA mutants, structural characterization |
651055 |
| 6.1.1.17 | more |
construction of a chimeric glutamyl:glutaminyl-tRNA synthetase, cGluGlnRS, consisting of the catalytic domain of the GluRS and the anti-codon binding domain of the GlnRS. In contrast to the isolated GluRS catalytic domain, the chimeric mutant shows detectable glutamylation activity with Escherichia coli tRNAGlu and is capable of complementing a ts-GluRS strain at non-permissive temperatures. The GlnRS anticodon-binding domain in cGluGlnRS enhances kcat for glutamylation, interaction analysis, overview |
690792 |
| 6.1.1.17 | more |
construction of constructed a chimaeric protein, cGluGlnRS, consisting of the catalytic domain, GluRS, and the anticodon binding domain of Escherichia coli GlnRS. cGluGlnRS shows detectable activity of glutamylation of Escherichia coli tRNAGlu and is capable of complementing an Escherichia coli temperature-sensitive GluRS strain at non-permissive temperatures. Both cGluGlnRS and N-terminal residues 1-314 of GluRS bind Escherichia coli tRNAglu with native GluRS-like affinity, suggesting that the anticodon-binding domain in cGluGlnRS enhances kcat for glutamylation. The kcat value of cGluGlnRS is approx. 500fold lower than that of GluRS, whereas the Km value is only moderately higher at the same solution conditions |
702120 |
| 6.1.1.17 | more |
construction of truncated enzyme GluRS-N, comprising residues 1-197, 17-207 and 1-207 |
671048 |
| 6.1.1.17 | more |
design of orthogonal tRNAs with sequences derived from archaeal tRNAs, 3 forms: 1. AQ(GU), i.e. archaeal glutaminyl with GU base pair at position 10-26, 2. AE(GU), i.e. archaeal glutamyl with GU base pair at position 10-28, 3. AE(GC), i.e. archaeal glutamyl with GC base pair at position 10-28 |
653391 |
| 6.1.1.17 | more |
generation of pZBD-chimeras of Ec-GluRS, four chimeric versions with partly replaced zinc-binding motif, pZBD. In the first chimera [Ec(Te)-GluRS], the pZBD of Ec-GluRS is replaced by the corresponding pZBD from Thermosynechococcus elongatus GluRS (Te-GluRS) whose structure is devoid of a bound Zn2+ despite containing the modified ZB-motif CxCxnYx3H. In the second chimera [Ec(EQRS)-GluRS] the pZBD of Ec-GluRS is replaced by the corresponding pZBD from Escherichia coli Glu-QRS (Ec-EQRS) whose zinc-bound structure contains the ZB-motif CxCxnYx3C. In the third chimera [Ec(Bt)-GluRS], the pZBD of Ec-GluRS is replaced by a 19-residue stretch from the pZBD of Bt-GluRS which contains a disrupted zinc binding motif CxMx20Yx3W and whose structure is devoid of a bound Zn2+ ion. The 19-residue stretch starts from the residue preceding the fourth zinc-co-ordinating cysteine residue in Ec-GluRS and continues until the last beta-strand of the pZBD fold. The overall secondary structure and compactness of wild-type Ec-GluRS remains unaltered in the chimeric constructs. The association of GluRS with tRNAGlu but not with ATP is sensitive to pZBD perturbations. Except for Ec(Bt)-GluRS, all pZBD-chimeras show 100fold or more reduced catalytic efficiency and contain zinc. Natively zinc-bound Ec-GluRS does not require zinc to be active |
744531 |
| 6.1.1.17 | more |
mutant enzymes with higher Km and lower turnover numbers |
209 |
