Aminoacyl Trna Synthetase
Mostrando 1-12 de 160 artigos, teses e dissertações.
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1. Characterization of the role of glutamyl-tRNA synthetase in the protein subcellular localization / Caracterização do papel da glutamil-tRNA sintetase na localização subcelular de proteínas
Nos organismos eucariotos, aproximadamente 50% das proteínas traduzidas no citoplasma são transportadas para as organelas, onde irão desempenhar suas funções. Com isso, surgiu um intricado sistema de transporte intracelular de proteínas. Nas plantas, a presença de uma segunda organela endossimbionte, o plastídio, tornou este sistema mais complexo e g
Publicado em: 2010
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2. Treonil-TRNA sintetase de germen de trigo : purificação e propriedades cineticas
Aminoacil - tRNA syntetases are enzymes that catalyse the first step of protein biosynthesis, the aminoacyl - tRNA formation. The substrates of the reaction are the L-aminoacid, ATP and tRNA, specific for this L-aminoacid. Magnesium ion parcipates as the cofactor of the reaction. The products of the reaction are aminoacyl - t.RNA, AMP and inorganic pyrophosp
Publicado em: 1991
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3. Engineering a tRNA and aminoacyl-tRNA synthetase for the site-specific incorporation of unnatural amino acids into proteins in vivo
In an effort to expand the scope of protein mutagenesis, we have completed the first steps toward a general method to allow the site-specific incorporation of unnatural amino acids into proteins in vivo. Our approach involves the generation of an “orthogonal” suppressor tRNA that is uniquely acylated in Escherichia coli by an engineered aminoacyl-tRNA sy
The National Academy of Sciences of the USA.
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4. High-molecular-weight forms of aminoacyl-tRNA synthetases and tRNA modification enzymes in Escherichia coli.
The presence of high-molecular-weight complexes of aminoacyl-tRNA synthetases in Escherichia coli has been reported (C. L. Harris, J. Bacteriol. 169:2718-2723, 1987). In the current study, Bio-Gel A-5M gel chromatography of 105,000 x g supernatant preparations from E. coli Q13 indicated high molecular weights for both tRNA methylase (300,000) and tRNA sulfur
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5. On the Conservation of Aminoacyl-Transfer Ribonucleic Acid Synthetase Genes in Bacillus
None of the heterologous deoxyribonucleic acid from various bacilli was capable of transforming lysyl- and tryptophanyl-transfer ribonucleic acid (tRNA) synthetase mutants of Bacillus subtilis to wild type. It was concluded that there is little conservation of the aminoacyl-tRNA synthetases even though the tRNA cistrons are conserved genetic functions.
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6. Aminoacyl-tRNA synthetase-induced cleavage of tRNA.
Aminoacyl-tRNA synthetases interact with their cognate tRNAs in a highly specific fashion. We have examined the phenomenon that upon complex formation E. coli glutaminyl-tRNA synthetase destabilizes tRNA(Gln) causing chain scissions in the presence of Mg2+ ions. The phosphodiester bond cleavage produces 3'-phosphate and 5'-hydroxyl ends. This kind of experim
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7. Characterization of Aminoacyl Transfer Ribonucleic Acid Formation Stimulated by Polyamines
From a comparative study of aminoacyl transfer ribonucleic acid (tRNA) formation stimulated by polyamines or by Mg2+, it is shown that both reactions have the same requirements for adenosine triphosphate, tRNA, and aminoacyl-tRNA synthetase. Reaction kinetics are similar in both reactions. The same tRNA is aminoacylated in the presence of either spermine of
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8. A truncated aminoacyl–tRNA synthetase modifies RNA
Aminoacyl–tRNA synthetases are modular enzymes composed of a central active site domain to which additional functional domains were appended in the course of evolution. Analysis of bacterial genome sequences revealed the presence of many shorter aminoacyl–tRNA synthetase paralogs. Here we report the characterization of a well conserved glutamyl–tRNA sy
National Academy of Sciences.
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9. Twenty-first aminoacyl-tRNA synthetase–suppressor tRNA pairs for possible use in site-specific incorporation of amino acid analogues into proteins in eukaryotes and in eubacteria
Two critical requirements for developing methods for the site-specific incorporation of amino acid analogues into proteins in vivo are (i) a suppressor tRNA that is not aminoacylated by any of the endogenous aminoacyl-tRNA synthetases (aaRSs) and (ii) an aminoacyl-tRNA synthetase that aminoacylates the suppressor tRNA but no other tRNA in the cell. Her
The National Academy of Sciences.
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10. A broadly applicable continuous spectrophotometric assay for measuring aminoacyl-tRNA synthetase activity.
We describe a convenient, simple and novel continuous spectrophotometric method for the determination of aminoacyl-tRNA synthetase activity. The assay relies upon the measurement of inorganic pyrophosphate generated in the first step of the aminoacylation of a tRNA. Pyrophosphate release is coupled to inorganic pyrophosphatase, to generate phosphate, which i
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11. Interaction of Escherichia coli tRNA(Ser) with its cognate aminoacyl-tRNA synthetase as determined by footprinting with phosphorothioate-containing tRNA transcripts.
A footprinting technique using phosphorothioate-containing RNA transcripts has been developed and applied to identify contacts between Escherichia coli tRNA(Ser) and its cognate aminoacyl-tRNA synthetase. The cloned gene for the tRNA was transcribed in four reactions in which a different NTP was complemented by 5% of the corresponding nucleoside 5'-O-(1-thio
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12. Transfer RNA identity contributes to transition state stabilization during aminoacyl-tRNA synthesis.
Sequence-specific interactions between aminoacyl-tRNA synthetases and their cognate tRNAs ensure both accurate RNA recognition and the efficient catalysis of aminoacylation. The effects of tRNA(Trp)variants on the aminoacylation reaction catalyzed by wild-type Escherichia coli tryptophanyl-tRNA synthe-tase (TrpRS) have now been investigated by stopped-flow f