Crystal structure of Nanoarchaeum equitans tyrosyl-tRNA synthetase and its aminoacylation activity toward tRNA Tyr with an extra guanosine residue at the 5'-terminus.
Horikoshi, T., Noguchi, H., Umehara, T., Mutsuro-Aoki, H., Kurihara, R., Noguchi, R., Hashimoto, T., Watanabe, Y., Ando, T., Kamata, K., Park, S.Y., Tamura, K.(2021) Biochem Biophys Res Commun 575: 90-95
- PubMed: 34461441 
- DOI: https://doi.org/10.1016/j.bbrc.2021.08.070
- Primary Citation of Related Structures:  
7FG6 - PubMed Abstract: 
tRNA Tyr of Nanoarchaeum equitans has a remarkable feature with an extra guanosine residue at the 5'-terminus. However, the N. equitans tRNA Tyr mutant without extra guanosine at the 5'-end was tyrosylated by tyrosyl-tRNA synthase (TyrRS). We solved the crystal structure of N. equitans TyrRS at 2.80 Å resolution. By comparing the present solved structure with the complex structures TyrRS with tRNA Tyr of Thermus thermophilus and Methanocaldococcus jannaschii, an arginine substitution mutant of N. equitans TyrRS at Ile200 (I200R), which is the putative closest candidate to the 5'-phosphate of C1 of N. equitans tRNA Tyr , was prepared. The I200R mutant tyrosylated not only wild-type tRNA Tyr but also the tRNA without the G-1 residue. Further tyrosylation analysis revealed that the second base of the anticodon (U35), discriminator base (A73), and C1:G72 base pair are strong recognition sites.
Organizational Affiliation: 
Department of Biological Science and Technology, Tokyo University of Science, 6-3-1 Niijuku, Katsushika-ku, Tokyo 125-8585, Japan.