4TQD

Crystal Structure of the C-terminal domain of IFRS bound with 3-iodo-L-Phe and ATP

4TQD の概要

• エントリーDOI: 10.2210/pdb4tqd/pdb
• 分子名称: Pyrrolysine--tRNA ligase, MAGNESIUM ION, ADENOSINE-5'-TRIPHOSPHATE, ... (6 entities in total)
• 機能のキーワード: amino acyl-trna synthetases, archaeal proteins, evolution, molecular, genetic code, substrate specificity, ligase
• 由来する生物種: Methanosarcina mazei
• 細胞内の位置: Cytoplasm : Q8PWY1
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 34704.88

構造登録者

Nakamura, A.,O'Donoghue, P.,Soll, D. (登録日: 2014-06-11, 公開日: 2014-11-12, 最終更新日: 2023-11-15)

主引用文献

Guo, L.T.,Wang, Y.S.,Nakamura, A.,Eiler, D.,Kavran, J.M.,Wong, M.,Kiessling, L.L.,Steitz, T.A.,O'Donoghue, P.,Soll, D.
Polyspecific pyrrolysyl-tRNA synthetases from directed evolution.
Proc.Natl.Acad.Sci.USA, 111:16724-16729, 2014

PubMed Abstract: Pyrrolysyl-tRNA synthetase (PylRS) and its cognate tRNA(Pyl) have emerged as ideal translation components for genetic code innovation. Variants of the enzyme facilitate the incorporation >100 noncanonical amino acids (ncAAs) into proteins. PylRS variants were previously selected to acylate N(ε)-acetyl-Lys (AcK) onto tRNA(Pyl). Here, we examine an N(ε)-acetyl-lysyl-tRNA synthetase (AcKRS), which is polyspecific (i.e., active with a broad range of ncAAs) and 30-fold more efficient with Phe derivatives than it is with AcK. Structural and biochemical data reveal the molecular basis of polyspecificity in AcKRS and in a PylRS variant [iodo-phenylalanyl-tRNA synthetase (IFRS)] that displays both enhanced activity and substrate promiscuity over a chemical library of 313 ncAAs. IFRS, a product of directed evolution, has distinct binding modes for different ncAAs. These data indicate that in vivo selections do not produce optimally specific tRNA synthetases and suggest that translation fidelity will become an increasingly dominant factor in expanding the genetic code far beyond 20 amino acids.

PubMed: 25385624
DOI: 10.1073/pnas.1419737111

実験手法

X-RAY DIFFRACTION (2.1429 Å)