Any feedback?
Please rate this page
(literature.php)
(0/150)

BRENDA support

Literature summary extracted from

  • Wu, J.; Fan, Y.; Ling, J.
    Mechanism of oxidant-induced mistranslation by threonyl-tRNA synthetase (2014), Nucleic Acids Res., 42, 6523-6531 .
    View publication on PubMedView publication on EuropePMC

Protein Variants

EC Number Protein Variants Comment Organism
6.1.1.3 C182A site-directed mutagenesis, the mutation leads to loss of editing activity and to Ser misacylation to tRNAThr. C182A and C182S mutations reduce the kcat value of editing over 500fold Escherichia coli
6.1.1.3 C182S site-directed mutagenesis, the mutation leads to loss of editing activity and to Ser misacylation to tRNAThr. C182A and C182S mutations reduce the kcat value of editing over 500fold Escherichia coli
6.1.1.3 H186A site-directed mutagenesis, the mutant does not show oxidation of Cys182 by H2O2 and only partially by NaOCl Escherichia coli
6.1.1.3 H73A site-directed mutagenesis, the mutant does not show oxidation of Cys182 by H2O2 and NaOCl Escherichia coli
6.1.1.3 H77A site-directed mutagenesis, the mutant shows oxidation of Cys182 by H2O2 and NaOCl Escherichia coli

Inhibitors

EC Number Inhibitors Comment Organism Structure
6.1.1.3 H2O2 oxidation of ThrRS by H2O2 causes editing defects and Ser misincorporation at Thr codons due to oxidation of Cys182, zinc or nickel ions inhibit C182 oxidation by hydrogen peroxide. Reducing the oxidized ThrRS with DTT or sodium arsenite (NaAsO2) recovers the editing activity, cysteine residue C182 is reversibly oxidized Escherichia coli

Localization

EC Number Localization Comment Organism GeneOntology No. Textmining
6.1.1.3 cytoplasm
-
 Escherichia coli 5737
-

Metals/Ions

EC Number Metals/Ions Comment Organism Structure
6.1.1.3 Mg2+ required Escherichia coli
6.1.1.3 Ni2+ the enzyme can bind one Ni2+ per subunit, binding of nickel inhibits the oxidation of enzyme residue Cys182 by H2O2 or air Escherichia coli
6.1.1.3 Zn2+ the enzyme can bind one Zn2+ per subunit, crystal structure analysis, PDB ID 1EVK, residues C334, H385 and H511 coordinate a zinc ion, which is essential for aminoacylation. Binding of zinc inhibits the oxidation of enzyme residue Cys182 by H2O2 or air Escherichia coli

Natural Substrates/ Products (Substrates)

EC Number Natural Substrates Organism Comment (Nat. Sub.) Natural Products Comment (Nat. Pro.) Rev. Reac.
6.1.1.3 ATP + L-threonine + tRNAThr Escherichia coli
-
 AMP + diphosphate + L-threonyl-tRNAThr
-
 ?

Organism

EC Number Organism UniProt Comment Textmining
6.1.1.3 Escherichia coli P0A8M3 MG1655 and KY2350
-

Substrates and Products (Substrate)

EC Number Substrates Comment Substrates Organism Products Comment (Products) Rev. Reac.
6.1.1.3 ATP + L-threonine + tRNAThr
-
 Escherichia coli AMP + diphosphate + L-threonyl-tRNAThr
-
 ?

Subunits

EC Number Subunits Comment Organism
6.1.1.3 dimer crystal structure analysis Escherichia coli

Synonyms

EC Number Synonyms Comment Organism
6.1.1.3 Threonyl-tRNA synthetase
-
 Escherichia coli
6.1.1.3 ThrRS
-
 Escherichia coli
6.1.1.3 ThrS
-
 Escherichia coli

Temperature Optimum [°C]

EC Number Temperature Optimum [°C] Temperature Optimum Maximum [°C] Comment Organism
6.1.1.3 37
-
 assay at Escherichia coli

pH Optimum

EC Number pH Optimum Minimum pH Optimum Maximum Comment Organism
6.1.1.3 7.2
-
 assay at Escherichia coli

Cofactor

EC Number Cofactor Comment Organism Structure
6.1.1.3 ATP
-
 Escherichia coli

General Information

EC Number General Information Comment Organism
6.1.1.3 malfunction threonyl-tRNA synthetase (ThrRS) misactivates serine and utilizes an editing site cysteine (C182 in Escherichia coli) to hydrolyze Ser-tRNAThr. Hydrogen peroxide oxidizes C182, leading to SertRNAThr production and mistranslation of threonine codons as serine. C182 is oxidized to sulfenic acid by air, hydrogen peroxide, and hypochlorite. Air oxidation increases the Ser-tRNAThr level in the presence of elongation factor Tu. C182 forms a putative metal binding site with three conserved histidine residues (H73, H77, and H186). H73 and H186, but not H77, are critical for activating C182 for oxidation. Zinc or nickel ions inhibit C182 oxidation by hydrogen peroxide. Bacteria may use ThrRS editing to sense the oxidant levels in the environment. C182 oxidation modeling, overview. C182 is directly activated by H73 and H186 rather than by a metal ion. Chronic oxidative stress leads to ThrRS mistranslation in vivo Escherichia coli
6.1.1.3 physiological function aminoacyl-tRNA synthetases maintain the fidelity during protein synthesis by selective activation of cognate amino acids at the aminoacylation site and hydrolysis of misformed aminoacyl-tRNAs at the editing site, crystal structure PDB ID 1TJE Escherichia coli