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2oiu
From Proteopedia
L1 Ribozyme Ligase circular adduct
Overview
Life originated, according to the RNA World hypothesis, from self-replicating ribozymes that catalyzed ligation of RNA fragments. We have solved the 2.6 angstrom crystal structure of a ligase ribozyme that catalyzes regiospecific formation of a 5' to 3' phosphodiester bond between the 5'-triphosphate and the 3'-hydroxyl termini of two RNA fragments. Invariant residues form tertiary contacts that stabilize a flexible stem of the ribozyme at the ligation site, where an essential magnesium ion coordinates three phosphates. The structure of the active site permits us to suggest how transition-state stabilization and a general base may catalyze the ligation reaction required for prebiotic RNA assembly.
About this Structure
Full crystallographic information is available from OCA.
Reference
The structural basis of ribozyme-catalyzed RNA assembly., Robertson MP, Scott WG, Science. 2007 Mar 16;315(5818):1549-53. PMID:17363667 Page seeded by OCA on Sun May 4 11:00:21 2008
