3OUY
How the CCA-adding Enzyme Selects Adenine Over Cytosine at Position 76 of tRNA
Summary for 3OUY
| Entry DOI | 10.2210/pdb3ouy/pdb |
| Related | 3OV7 3OVA 3OVB 3OVS |
| Descriptor | CCA-Adding Enzyme, RNA (35-MER), SULFATE ION, ... (7 entities in total) |
| Functional Keywords | protein-rna complex, rossmann fold, cca-adding, trna, phospholation, transferase-rna complex, transferase/rna |
| Biological source | Archaeoglobus fulgidus More |
| Total number of polymer chains | 4 |
| Total formula weight | 126414.38 |
| Authors | Pan, B.C.,Xiong, Y.,Steitz, T.A. (deposition date: 2010-09-15, release date: 2010-12-01, Last modification date: 2024-02-21) |
| Primary citation | Pan, B.,Xiong, Y.,Steitz, T.A. How the CCA-Adding Enzyme Selects Adenine over Cytosine at Position 76 of tRNA. Science, 330:937-940, 2010 Cited by PubMed Abstract: CCA-adding enzymes [ATP(CTP):tRNA nucleotidyltransferases] add CCA onto the 3' end of transfer RNA (tRNA) precursors without using a nucleic acid template. Although the mechanism by which cytosine (C) is selected at position 75 of tRNA has been established, the mechanism by which adenine (A) is selected at position 76 remains elusive. Here, we report five cocrystal structures of the enzyme complexed with both a tRNA mimic and nucleoside triphosphates under catalytically active conditions. These structures suggest that adenosine 5'-monophosphate is incorporated onto the A76 position of the tRNA via a carboxylate-assisted, one-metal-ion mechanism with aspartate 110 functioning as a general base. The discrimination against incorporation of cytidine 5'-triphosphate (CTP) at position 76 arises from improper placement of the α phosphate of the incoming CTP, which results from the interaction of C with arginine 224 and prevents the nucleophilic attack by the 3' hydroxyl group of cytidine75. PubMed: 21071662DOI: 10.1126/science.1194985 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (2.69 Å) |
Structure validation
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