1ou5 is a 2 chain structure with sequence from Homo sapiens. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
All tRNA molecules carry the invariant sequence CCA at their 3'-terminus for amino acid attachment. The post-transcriptional addition of CCA is carried out by ATP(CTP):tRNA nucleotidyltransferase, also called CCase. This enzyme catalyses a unique template-independent but sequence-specific nucleotide polymerization reaction. In order to reveal the molecular mechanism of this activity, we solved the crystal structure of human CCase by single isomorphous replacement. The structure reveals a four domain architecture with a cluster of conserved residues forming a positively charged cleft between the first two domains. Structural homology of the N-terminal CCase domain to other nucleotidyltransferases could be exploited for modeling a tRNA-substrate complex. The model places the tRNA 3'-end into the N-terminal nucleotidyltransferase site, close to a patch of conserved residues that provide the binding sites for CTP and ATP. Based on our results, we introduce a corkscrew model for CCA addition that includes a fixed active site and a traveling tRNA-binding region formed by flexible parts of the protein.
Crystal structure of the human CCA-adding enzyme: insights into template-independent polymerization.,Augustin MA, Reichert AS, Betat H, Huber R, Morl M, Steegborn C J Mol Biol. 2003 May 16;328(5):985-94. PMID:12729736[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
↑ Augustin MA, Reichert AS, Betat H, Huber R, Morl M, Steegborn C. Crystal structure of the human CCA-adding enzyme: insights into template-independent polymerization. J Mol Biol. 2003 May 16;328(5):985-94. PMID:12729736