2024-03-29T06:26:54Zhttps://eprints.lib.hokudai.ac.jp/dspace-oai/requestoai:eprints.lib.hokudai.ac.jp:2115/170872022-11-17T02:08:08Zhdl_2115_20055hdl_2115_8527The structure of Pyrococcus horikoshii 2'-5' RNA ligase at 1.94Å resolution reveals a possible open form with a wider active-site cleftGao, Yong-GuiYao, MinOkada, AyukoTanaka, Isao2'-5' RNA ligase2H phosphoesterase superfamilyPyrococcus horikoshii464Bacterial and archaeal 2'-5' RNA ligases, members of the 2H phosphoesterase superfamily, catalyze the linkage of the 5' and 3' exons via a 2'-5'-phosphodiester bond during tRNA-precursor splicing. The crystal structure of the 2'-5' RNA ligase PH0099 from Pyrococcus horikoshii OT3 was solved at 1.94 Å resolution (PDB code 1vgj). The molecule has a bilobal α+β arrangement with two antiparallel β-sheets constituting a V-shaped active-site cleft, as found in other members of the 2H phosphoesterase superfamily. The present structure was significantly different from that determined previously at 2.4 Å resolution (PDB code 1vdx) in the active-site cleft; the entrance to the cleft is wider and the active site is easily accessible to the substrate (RNA precursor) in our structure. Structural comparison with the 2'-5' RNA ligase from Thermus thermophilus HB8 also revealed differences in the RNA precursor-binding region. The structural differences in the active-site residues (tetrapeptide motifs H-X-T/S-X) between the members of the 2H phosphoesterase superfamily are discussed.Blackwell PublishingJournal Articleapplication/pdfhttp://hdl.handle.net/2115/17087https://eprints.lib.hokudai.ac.jp/dspace/bitstream/2115/17087/1/ACSF-SB%26CC62-12.pdf1744-3091Acta Crystallographica Section F Structural Biology and Crystallization Communications6212119612002006-12-01enginfo:pmid/17142895info:doi/10.1107/S1744309106046616publisher