부산대학교 도서관

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.bbrc.2005.11.007 Byline: Souta Horie (a), Yoshiya Ikawa (b), Tan Inoue (a) Keywords: Ribozyme; Kinetic analysis; Structural analysis; RNA ligase; Mechanism Abstract: We recently reported on the molecular design and synthesis of a new RNA ligase ribozyme (DSL), whose active site was selected from a sequence library consisting of 30 random nucleotides set on a defined 3D structure of a designed RNA scaffold. In this study, we report on the structural and biochemical analyses of DSL. Structural analysis indicates that the active site, which consists of the selected sequence, attaches to the folded scaffold as designed. To see whether DSL resembles known ribozymes, a biochemical assay was performed. Metal-dependent kinetic studies suggest that the ligase requires Mg.sup.2+ ions. The replacement of Mg.sup.2+ with Co(NH.sub.3).sub.6.sup.3+ prohibits the reaction, indicating that DSL requires innersphere coordination of Mg.sup.2+ for a ligation reaction. The results show that DSL has requirements similar to those of previously reported catalytic RNAs. Author Affiliation: (a) Graduate School of Biostudies, Kyoto University, Kyoto 606-8502, Japan (b) Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, 819-0395 Fukuoka, Japan Article History: Received 25 October 2005 Article Note: (footnote) [star] Abbreviations: DSL, designed and selected ligase; Tris, tris(hydroxymethyl)aminomethane; DMS, dimethyl sulfate.