Threonyl-tRNA synthetase from Thermus thermophilus: purification and some structural and kinetic properties
Autor: | Daniel Kern, Joseph Reinbolt, E Melnikova, M. B. Garber, J Zheltonosova, Chantal Ehresmann, Bernard Ehresmann |
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Rok vydání: | 1994 |
Předmět: |
Aspartate—tRNA ligase
Aspartate-tRNA Ligase Molecular Sequence Data Aminoacylation medicine.disease_cause environment and public health Biochemistry Chromatography Affinity Phenylalanine—tRNA ligase medicine Escherichia coli Threonine-tRNA Ligase TRNA aminoacylation Amino Acid Sequence biology Sequence Homology Amino Acid Thermus thermophilus food and beverages General Medicine biology.organism_classification enzymes and coenzymes (carbohydrates) Threonine—tRNA ligase Kinetics Transfer RNA biology.protein Chromatography Gel bacteria Electrophoresis Polyacrylamide Gel Phenylalanine-tRNA Ligase Sequence Alignment |
Zdroj: | Biochimie. 76(1) |
ISSN: | 0300-9084 |
Popis: | Threonyl-tRNA synthetase (ThrRS) has been isolated from an extreme thermophile Thermus thermophilus strain HB8. The enzyme was purified to electrophoretic homogeneity by combinations of column chromatographies on DEAE-Sepharose, S-Sepharose, ACA-44 Ultrogel and HA-Ultrogel. Seventeen mg of purified enzyme were obtained from 1 kg of biomass. In parallel, purified aspartyl- and phenylalanyl-tRNA synthetases were obtained. The purified ThrRS is composed of two identical subunits with a molecular mass of about 77,000 (virtually the same as E coli ThrRS). The N-terminal sequence has been determined. The homology between the first 45 amino acid residues of ThrRS from T thermophilus and E coli is about 29%. A comparative study of tRNA(Thr) charging by ThrRS from E coli and T thermophilus reveals a similar efficiency of the reaction in both homologous systems. This efficiency remains unchanged for aminoacylation of tRNA(Thr) from T thermophilus by the heterologous ThrRS from E coli, but decreases 700 times for aminoacylation of E coli tRNA(Thr) by ThrRS from T thermophilus. |
Databáze: | OpenAIRE |
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