1IT8

Crystal structure of archaeosine tRNA-guanine transglycosylase from Pyrococcus horikoshii complexed with archaeosine precursor, preQ0

1IT8 の概要

• エントリーDOI: 10.2210/pdb1it8/pdb
• 関連するPDBエントリー: 1IQ8 1IT7
• 分子名称: archaeosine tRNA-guanine transglycosylase, ZINC ION, MAGNESIUM ION, ... (5 entities in total)
• 機能のキーワード: (alpha/beta)8 barrel, riken structural genomics/proteomics initiative, rsgi, structural genomics, transferase
• 由来する生物種: Pyrococcus horikoshii
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 133754.86

構造登録者

Ishitani, R.,Nureki, O.,Fukai, S.,Kijimoto, T.,Nameki, N.,Watanabe, M.,Kondo, H.,Sekine, M.,Okada, N.,Nishimura, S.,Yokoyama, S.,RIKEN Structural Genomics/Proteomics Initiative (RSGI) (登録日: 2002-01-11, 公開日: 2002-05-22, 最終更新日: 2023-10-25)

主引用文献

Ishitani, R.,Nureki, O.,Fukai, S.,Kijimoto, T.,Nameki, N.,Watanabe, M.,Kondo, H.,Sekine, M.,Okada, N.,Nishimura, S.,Yokoyama, S.
Crystal structure of archaeosine tRNA-guanine transglycosylase.
J.Mol.Biol., 318:665-677, 2002

PubMed Abstract: Archaeosine tRNA-guanine transglycosylase (ArcTGT) catalyzes the exchange of guanine at position 15 in the D-loop of archaeal tRNAs with a free 7-cyano-7-deazaguanine (preQ(0)) base, as the first step in the biosynthesis of an archaea-specific modified base, archaeosine (7-formamidino-7-deazaguanosine). We determined the crystal structures of ArcTGT from Pyrococcus horikoshii at 2.2 A resolution and its complexes with guanine and preQ(0), at 2.3 and 2.5 A resolutions, respectively. The N-terminal catalytic domain folds into an (alpha/beta)(8) barrel with a characteristic zinc-binding site, showing structural similarity with that of the bacterial queuosine TGT (QueTGT), which is involved in queuosine (7-[[(4,5-cis-dihydroxy-2-cyclopenten-1-yl)-amino]methyl]-7-deazaguanosine) biosynthesis and targets the tRNA anticodon. ArcTGT forms a dimer, involving the zinc-binding site and the ArcTGT-specific C-terminal domain. The C-terminal domains have novel folds, including an OB fold-like "PUA domain", whose sequence is widely conserved in eukaryotic and archaeal RNA modification enzymes. Therefore, the C-terminal domains may be involved in tRNA recognition. In the free-form structure of ArcTGT, an alpha-helix located at the rim of the (alpha/beta)(8) barrel structure is completely disordered, while it is ordered in the guanine-bound and preQ(0)-bound forms. Structural comparison of the ArcTGT.preQ(0), ArcTGT.guanine, and QueTGT.preQ(1) complexes provides novel insights into the substrate recognition mechanisms of ArcTGT.

PubMed: 12054814
DOI: 10.1016/S0022-2836(02)00090-6

実験手法

X-RAY DIFFRACTION (2.5 Å)