Titelangaben
Augustin, Martin A. ; Reichert, Andreas S. ; Betat, Heike ; Huber, Robert ; Mörl, Mario ; Steegborn, Clemens:
Crystal structure of the human CCA-adding enzyme: insights into template-independent polymerization.
In: Journal of Molecular Biology.
Bd. 328
(2003)
Heft 5
.
- S. 985-994.
ISSN 0022-2836
DOI: https://doi.org/10.1016/S0022-2836(03)00381-4
Abstract
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.
Weitere Angaben
Publikationsform: | Artikel in einer Zeitschrift |
---|---|
Begutachteter Beitrag: | Ja |
Zusätzliche Informationen: | PubMed-ID: 12729736 |
Institutionen der Universität: | Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften > Fachgruppe Chemie > Lehrstuhl Biochemie > Lehrstuhl Biochemie I - Proteinbiochemie der Signaltransduktion - Univ.-Prof. Dr. Clemens Steegborn Fakultäten Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften > Fachgruppe Chemie Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften > Fachgruppe Chemie > Lehrstuhl Biochemie |
Titel an der UBT entstanden: | Nein |
Themengebiete aus DDC: | 500 Naturwissenschaften und Mathematik > 540 Chemie |
Eingestellt am: | 13 Apr 2015 11:07 |
Letzte Änderung: | 08 Jul 2022 13:46 |
URI: | https://eref.uni-bayreuth.de/id/eprint/10111 |