5T5A
Crystal Structure of the Twister Sister (TS) Ribozyme at 2.0 Angstrom
Summary for 5T5A
| Entry DOI | 10.2210/pdb5t5a/pdb |
| Descriptor | DNA/RNA (71-MER), MAGNESIUM ION (3 entities in total) |
| Functional Keywords | rna junction catalysis, rna |
| Biological source | metagenome More |
| Total number of polymer chains | 1 |
| Total formula weight | 20355.50 |
| Authors | Lilley, D.M.J.,Liu, Y.,Wilson, T.J. (deposition date: 2016-08-30, release date: 2017-03-08, Last modification date: 2024-05-08) |
| Primary citation | Liu, Y.,Wilson, T.J.,Lilley, D.M. The structure of a nucleolytic ribozyme that employs a catalytic metal ion. Nat. Chem. Biol., 13:508-513, 2017 Cited by PubMed Abstract: The TS ribozyme (originally called "twister sister") is a catalytic RNA. We present a crystal structure of the ribozyme in a pre-reactive conformation. Two co-axial helical stacks are organized by a three-way junction and two tertiary contacts. Five divalent metal ions are directly coordinated to RNA ligands, making important contributions to the RNA architecture. The scissile phosphate lies in a quasihelical loop region that is organized by a network of hydrogen bonding. A divalent metal ion is directly bound to the nucleobase 5' to the scissile phosphate, with an inner-sphere water molecule positioned to interact with the O2' nucleophile. The rate of ribozyme cleavage correlated in a log-linear manner with divalent metal ion pK, consistent with proton transfer in the transition state, and we propose that the bound metal ion is a likely general base for the cleavage reaction. Our data indicate that the TS ribozyme functions predominantly as a metalloenzyme. PubMed: 28263963DOI: 10.1038/nchembio.2333 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (2 Å) |
Structure validation
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