4RDX

Structure of histidinyl-tRNA synthetase in complex with tRNA(His)

Summary for 4RDX

• Entry DOI: 10.2210/pdb4rdx/pdb
• Descriptor: Histidine--tRNA ligase, tRNA(his), ADENOSINE MONOPHOSPHATE, ... (5 entities in total)
• Functional Keywords: aminoacyl-trna synthetase, classii aars, aminoacylation, histidine, trna, ligase-rna complex, ligase/rna
• Biological source: Thermus thermophilus HB27; More
• Cellular location: Cytoplasm : P62374
• Total number of polymer chains: 2
• Total formula weight: 73095.40

Authors

Xie, W.,Tian, Q.,Wang, C. (deposition date: 2014-09-20, release date: 2015-03-25, Last modification date: 2023-11-08)

Primary citation

Tian, Q.,Wang, C.,Liu, Y.,Xie, W.
Structural basis for recognition of G-1-containing tRNA by histidyl-tRNA synthetase
Nucleic Acids Res., 43:2980-2990, 2015

PubMed Abstract: Aminoacyl-tRNA synthetases (aaRSs) play a crucial role in protein translation by linking tRNAs with cognate amino acids. Among all the tRNAs, only tRNA(His) bears a guanine base at position -1 (G-1), and it serves as a major recognition element for histidyl-tRNA synthetase (HisRS). Despite strong interests in the histidylation mechanism, the tRNA recognition and aminoacylation details are not fully understood. We herein present the 2.55 Å crystal structure of HisRS complexed with tRNA(His), which reveals that G-1 recognition is principally nonspecific interactions on this base and is made possible by an enlarged binding pocket consisting of conserved glycines. The anticodon triplet makes additional specific contacts with the enzyme but the rest of the loop is flexible. Based on the crystallographic and biochemical studies, we inferred that the uniqueness of histidylation system originates from the enlarged binding pocket (for the extra base G-1) on HisRS absent in other aaRSs, and this structural complementarity between the 5' extremity of tRNA and enzyme is probably a result of coevolution of both.

PubMed: 25722375
DOI: 10.1093/nar/gkv129

Experimental method

X-RAY DIFFRACTION (2.55 Å)