Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
1998-3-2
pubmed:abstractText
Glutamyl-tRNA synthetase (GluRS) belongs to the class I aminoacyl-tRNA synthetases and shows several similarities with glutaminyl-tRNA synthetase concerning structure and catalytic properties. Phylogenetic studies suggested that both diverged from an ancestral glutamyl-tRNA synthetase responsible for the gluta-mylation of tRNA(Glu) and tRNA(Gln), and whose Glu-tRNA(Gln) product is transformed into Gln-tRNA(Gln) by a specific amidotransferase. This pathway is present in gram-positive and some gram-negative eubacteria, in some archae and in organelles, and was never found jointly with a glutaminyl-tRNA synthetase. Other gram-negative eubacteria and the cytoplasm of eukaryotes contain a glutamyl-tRNA synthetase specific for tRNA(Glu), and a glutaminyl-tRNA synthetase. Bacterial glutamyl-tRNA synthetases consist of about 500 amino acid residues, possess molecular masses of about 50 kDa, and act as monomers. In higher eukaryotes chimeric glutamyl-prolyl-tRNA synthetases were found, in a high molecular mass complex containing several other aminoacyl-tRNA synthetases. To date one crystal structure of a glutamyl-tRNA synthetase (Thermus thermophilus) has been solved. The molecule has the form of a bent cylinder and consists of four domains. The N-terminal half (domains 1 and 2) contains the 'Rossman fold' typical for class I synthetases and resembles the corresponding part of E. coli GlnRS, whereas the C-terminal half exhibits a GluRS-specific structure. As found for the other aminoacyl-tRNA synthetases the catalytic pathway of GluRS includes the formation of an aminoacyl adenylate in the first reaction step, but GluRS shares a special property with GlnRS and ArgRS: the ATP/PPi pyrophosphate exchange reaction is only catalyzed in the presence of the cognate tRNA. Compared with other aminoacyl-tRNA synthetases a relatively high number of investigations deals with recognition of tRNA(Glu) by GluRS. Besides interactions between the enzyme and the acceptor stem and the anticodon of tRNA(Glu), checking of the dihydrouridine arm and of the variable loop by GluRS are documented.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
1431-6730
pubmed:author
pubmed:issnType
Print
pubmed:volume
378
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1313-29
pubmed:dateRevised
2004-11-17
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Glutamyl-tRNA sythetase.
pubmed:affiliation
Max-Planck-Institut für experimentelle Medizin, Göttingen, Germany.
pubmed:publicationType
Journal Article, Review