1UET

Divergent evolutions of trinucleotide polymerization revealed by an archaeal CCA-adding enzyme structure

Summary for 1UET

• Entry DOI: 10.2210/pdb1uet/pdb
• Related: 1UEU 1UEV
• Descriptor: tRNA nucleotidyltransferase, ACETATE ION, CALCIUM ION, ... (5 entities in total)
• Functional Keywords: transferase, riken structural genomics/proteomics initiative, rsgi, structural genomics
• Biological source: Archaeoglobus fulgidus
• Total number of polymer chains: 1
• Total formula weight: 51672.72

Authors

Nureki, O.,RIKEN Structural Genomics/Proteomics Initiative (RSGI) (deposition date: 2003-05-21, release date: 2003-12-02, Last modification date: 2023-12-27)

Primary citation

Okabe, M.,Tomita, K.,Ishitani, R.,Ishii, R.,Takeuchi, N.,Arisaka, F.,Nureki, O.,Yokoyama, S.
Divergent evolutions of trinucleotide polymerization revealed by an archaeal CCA-adding enzyme structure.
Embo J., 22:5918-5927, 2003

PubMed Abstract: CCA-adding enzyme [ATP(CTP):tRNA nucleotidyltransferase], a template-independent RNA polymerase, adds the defined 'cytidine-cytidine-adenosine' sequence onto the 3' end of tRNA. The archaeal CCA-adding enzyme (class I) and eubacterial/eukaryotic CCA-adding enzyme (class II) show little amino acid sequence homology, but catalyze the same reaction in a defined fashion. Here, we present the crystal structures of the class I archaeal CCA-adding enzyme from Archaeoglobus fulgidus, and its complexes with CTP and ATP at 2.0, 2.0 and 2.7 A resolutions, respectively. The geometry of the catalytic carboxylates and the relative positions of CTP and ATP to a single catalytic site are well conserved in both classes of CCA-adding enzymes, whereas the overall architectures, except for the catalytic core, of the class I and class II CCA-adding enzymes are fundamentally different. Furthermore, the recognition mechanisms of substrate nucleotides and tRNA molecules are distinct between these two classes, suggesting that the catalytic domains of class I and class II enzymes share a common origin, and distinct substrate recognition domains have been appended to form the two presently divergent classes.

PubMed: 14592988
DOI: 10.1093/emboj/cdg563

Experimental method

X-RAY DIFFRACTION (2 Å)