These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Asparaginyl-tRNA synthetase from Thermus thermophilus HB8. Sequence of the gene and crystallization of the enzyme expressed in Escherichia coli.
    Author: Seignovert L, Härtlein M, Leberman R.
    Journal: Eur J Biochem; 1996 Jul 15; 239(2):501-8. PubMed ID: 8706760.
    Abstract:
    The gene for the asparaginyl-tRNA synthetase, a class IIb enzyme, from the extreme thermophile Thermus thermophilus HB8 has been cloned and sequenced. Sequence analysis revealed an open reading frame that codes for a protein of 438 amino acid residues (50875 Da). Codon usage in the asparaginyl-tRNA synthetase gene (asnS) is similar to the characteristic usage in the genes for proteins from bacteria of the genus Thermus, and the G+C content in the third position of the codons is as high as 94%. The amino acid sequence of asparaginyl-tRNA synthetase from T. thermophilus shows high similarity with other bacterial asparaginyl-tRNA synthetase sequences (30-55% identity). By expression of the T. thermophilus asnS gene in Escherichia coli, the thermostable enzyme was overproduced and purified to homogeneity by heat treatment and two chromatography steps. The protein obtained is remarkably thermostable and retains 50% of its initial tRNA aminoacylation activity after 1 h of incubation at 90 degrees C or 21 h at 85 degrees C. Crystals of the enzyme were obtained from polyethylene glycol 6000 solutions by vapour diffusion techniques. The crystals diffract X-rays beyond 2.8 A.
    [Abstract] [Full Text] [Related] [New Search]