Selenophosphate Synthetase
Mostrando 1-12 de 20 artigos, teses e dissertações.
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1. Biophysical studies of Escherichia coli Selenophosphate Synthetase and investigation of its role in the Selenocysteine biosynthesis pathway / Estudos biofísicos da Selenofosfato Sintetase de Escherichia coli e investigação de seu papel na via de biossíntese de Selenocisteínas
A principal forma biológica do selênio em vários organismos é o aminoácido Selenocisteína (Sec, U), que é incorporado em um polipeptídio emergente em códons UGA específicos. Em Escherichia coli, esta incorporação requer os genes que codificam para Seril-tRNA Sintetase (SerRS), Selenocisteína Sintase (SELA), um tRNASec específico (SELC), Selenof
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 30/01/2012
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2. Estudos moleculares das enzimas envolvidas na biossíntese de selenocisteína em Trypanosoma brucei e Leishmania major / Molecular studies of the enzymes involved in selenocysteine synthesis in Trypanosoma brucei and Leishmania major
One of the main biological forms of the selenium incorporation is the amino acid form named selenocysteine (Sec, U), which is incorporated co-translationally at the emerging new polypeptide in the specific positions at the UGA codon, that is usually recognized as stop codon. The incorporation of the selenocysteine in E.coli is already solved with the involve
Publicado em: 2008
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3. Estudos moleculares da Selenocisteína Sintase (SELA) de Escherichia coli.
The study of translation processes attracts the interest of a wide range of research groups due to its main role in general cellular metabolism. In particular, the investigation of new amino acid residues, such as selenocysteine and pyrrolysin, which result in an expansion of the genetic code from the traditional 20 residues to a total of 22 residues up to t
Publicado em: 2005
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4. Selenophosphate synthetase: detection in extracts of rat tissues by immunoblot assay and partial purification of the enzyme from the archaean Methanococcus vannielii.
In Escherichia coli and Salmonella typhimurium it has been shown that selenophosphate serves as the selenium donor for the conversion of seryl-tRNA to selenocysteyl-tRNA and for the synthesis of 2-selenouridine, a modified nucleoside present in tRNAs. Although selenocysteyl-tRNA also is formed in eukaryotes and is used for the specific insertion of selenocys
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5. Structure of an N-terminally truncated selenophosphate synthetase from Aquifex aeolicus
The crystal structure of an N-terminally (25 residues) truncated fragment of selenophosphate synthetase (SPS-ΔN) from Aquifex aeolicus has been determined at 2.0 Å resolution.
International Union of Crystallography.
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6. Effects of monovalent cations and divalent metal ions on Escherichia coli selenophosphate synthetase.
A labile selenium donor compound, selenophosphate, is formed from selenide and ATP by selenophosphate synthetase. A divalent metal ion, Mg2+, and a monovalent cation, K+, NH4+, or Rb+, are required for selenophosphate synthetase activity [Veres, Z., Kim, I. Y., Scholz, T. D. & Stadtman, T. C. (1994) J. Biol. Chem. 269, 10597-10603]. Na+ and Li+ are ineffecti
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7. Catalytic properties of selenophosphate synthetases: Comparison of the selenocysteine-containing enzyme from Haemophilus influenzae with the corresponding cysteine-containing enzyme from Escherichia coli
The selD gene from Haemophilus influenzae has been overexpressed in Escherichia coli. The expressed protein was purified to homogeneity in a four-step procedure and then carboxymethylated by reaction with chloroacetate. N-terminal sequencing by Edman degradation identified residue 16 as carboxymethyl selenocysteine, which corresponded to the essential cystei
National Academy of Sciences.
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8. Isotope exchange studies on the Escherichia coli selenophosphate synthetase mechanism
Selenophosphate synthetase, the Escherichia coli selD gene product, is a 37-kDa protein that catalyzes the synthesis of selenophosphate from ATP and selenide. In the absence of selenide, ATP is converted quantitatively to AMP and two orthophosphates in a very slow partial reaction. A monophosphorylated enzyme derivative containing the γ-phosphoryl group of
National Academy of Sciences.
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9. Fetal mouse selenophosphate synthetase 2 (SPS2): Characterization of the cysteine mutant form overproduced in a baculovirus–insect cell system
A novel gene detected in mouse embryonic sites of hematopoiesis was cloned and shown to be a eukaryotic analog of the Escherichia coli selenophosphate synthetase gene. Unlike the E. coli enzyme, which is not a selenoprotein, the presence of selenocysteine in the mouse enzyme is indicated by a TGA codon in the open reading frame of the gene in a position corr
The National Academy of Sciences of the USA.
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10. A DNA replication-related element downstream from the initiation site of Drosophila selenophosphate synthetase 2 gene is essential for its transcription
Selenophosphate synthetase catalyzes the synthesis of selenophosphate which is a selenium donor for Sec biosynthesis. In Drosophila melanogaster, there are two types of selenophosphate synthetases designated dSPS1 and dSPS2, where dSPS2 is a selenoprotein. The mechanism of gene expression of dSPS2 as well as other selenoproteins in Drosophila has not been el
Oxford University Press.
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11. Characterization of potential selenium-binding proteins in the selenophosphate synthetase system
Selenophosphate, an activated form of selenium that can serve as a selenium donor, is generated by the selD gene product, selenophosphate synthetase (SPS). Selenophosphate is required by several bacteria and by mammals for the specific synthesis of Secys-tRNA, the precursor of selenocysteine in selenoenzymes. Although free selenide can be used in vitro for s
National Academy of Sciences.
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12. Selenium Is Mobilized In Vivo from Free Selenocysteine and Is Incorporated Specifically into Formate Dehydrogenase H and tRNA Nucleosides
Selenophosphate synthetase (SPS), the selD gene product from Escherichia coli, catalyzes the biosynthesis of monoselenophosphate, AMP, and orthophosphate in a 1:1:1 ratio from selenide and ATP. It was recently demonstrated that selenium delivered from selenocysteine by an E. coli NifS-like protein could replace free selenide in the in vitro SPS assay for sel
American Society for Microbiology.