Summary information and primary citation
- PDB-id
- 4x0b; SNAP-derived features in text and JSON formats;
DNAproDB
- Class
- transferase-RNA
- Method
- X-ray (3.2 Å)
- Summary
- Structure of trna-processing enzyme complex 7
- Reference
- Yamashita S, Martinez A, Tomita K (2015): "Measurement of Acceptor-T Psi C Helix Length of tRNA for Terminal A76-Addition by A-Adding Enzyme." Structure, 23, 830-842. doi: 10.1016/j.str.2015.03.013.
- Abstract
- The 3'-terminal CCA (C74C75A76-3') of tRNA is required for protein synthesis. In Aquifex aeolicus, the CCA-3' is synthesized by CC-adding and A-adding enzymes, although in most organisms, CCA is synthesized by a single CCA-adding enzyme. The mechanisms by which the A-adding enzyme adds only A76, but not C74C75, onto tRNA remained elusive. The complex structures of the enzyme with various tRNAs revealed the presence of a single tRNA binding site on the enzyme, with the enzyme measuring the acceptor-TΨC helix length of tRNA. The 3'-C75 of tRNA lacking A76 can reach the active site and the size and shape of the nucleotide binding pocket at the insertion stage are suitable for ATP. The 3'-C74 of tRNA lacking C75A76 cannot reach the active site, although CTP or ATP can bind the active pocket. Thus, the A-adding enzyme adds only A76, but not C74C75, onto tRNA.
