The crystal structure of leucyl-tRNA synthetase complexed with tRNALeu in the post-transfer-editing conformation

Nat Struct Mol Biol. 2005 Oct;12(10):923-30. doi: 10.1038/nsmb986. Epub 2005 Sep 11.

Abstract

Leucyl-tRNA synthetase (LeuRS) has a specific post-transfer editing activity directed against mischarged isoleucine and similar noncognate amino acids. We describe the post-transfer-editing and product complexes of Thermus thermophilus LeuRS (LeuRSTT) with tRNA(Leu) at 2.9- to 3.3-A resolution. In the post-transfer-editing configuration, A76 binds in the editing active site exactly as previously found for the adenosine moiety of a small-molecule editing-substrate analog. The 60 C-terminal residues of LeuRSTT, unseen in previous structures, fold into a compact domain flexibly linked to the rest of the molecule and interacting with the G19-C56 tertiary base pair of tRNA(Leu). LeuRS recognition of tRNA(Leu) depends essentially on tRNA shape rather than base-specific interactions. The structures show that considerable domain rotations, notably of the editing domain, accompany the tRNA-3' end dynamics associated successively with aminoacylation, post-transfer editing and product release.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Crystallography, X-Ray
  • Molecular Sequence Data
  • Nucleic Acid Conformation
  • Protein Conformation
  • RNA Editing*
  • RNA, Transfer, Amino Acyl / chemistry*
  • RNA, Transfer, Leu / chemistry*
  • Thermus thermophilus / enzymology*
  • Thermus thermophilus / genetics*
  • Transfer RNA Aminoacylation*

Substances

  • RNA, Transfer, Amino Acyl
  • RNA, Transfer, Leu

Associated data

  • PDB/1H3N
  • PDB/2BTE
  • PDB/2BYT