1EQR

CRYSTAL STRUCTURE OF FREE ASPARTYL-TRNA SYNTHETASE FROM ESCHERICHIA COLI

Summary for 1EQR

• Entry DOI: 10.2210/pdb1eqr/pdb
• Related: 1C0A
• Descriptor: ASPARTYL-TRNA SYNTHETASE, MAGNESIUM ION (3 entities in total)
• Functional Keywords: domains, anti-parallel beta strand, beta barrel, oligomer binding fold, ligase
• Biological source: Escherichia coli
• Total number of polymer chains: 3
• Total formula weight: 198061.85

Authors

Rees, B.,Webster, G.,Delarue, M.,Boeglin, M.,Moras, D. (deposition date: 2000-04-06, release date: 2000-06-29, Last modification date: 2024-04-03)

Primary citation

Rees, B.,Webster, G.,Delarue, M.,Boeglin, M.,Moras, D.
Aspartyl tRNA-synthetase from Escherichia coli: flexibility and adaptability to the substrates.
J.Mol.Biol., 299:1157-1164, 2000

PubMed Abstract: The crystal structure of aspartyl-tRNA synthetase from Escherichia coli has been determined to a resolution of 2.7 A. The structure is compared to the same enzyme co-crystallized with tRNA(Asp) and containing aspartyl adenylate or ATP. The asymmetric unit contains three monomers of the enzyme. While most parts of the protein show no significant differences in the three monomers, a few regions cannot be superimposed. Those regions are characterized by a high B-factor, and consist mostly of loops that make contacts with the tRNA in the complexes. The flexibility of the protein is seen at a global level, by the observation of a 10 to 15 degrees rotation of the N-terminal and insertion domains upon tRNA binding, and at the level of the individual amino acid residues, by main-chain and side-chain rearrangements. In contrast to these induced-fit conformational changes, a few residues essential for the tRNA anticodon or aspartyl-adenylate recognition exist in a predefined conformation, ensured by specific interactions within the protein.

PubMed: 10873442
DOI: 10.1006/jmbi.2000.3792

Experimental method

X-RAY DIFFRACTION (2.7 Å)