1y0q
From Proteopedia
Crystal structure of an active group I ribozyme-product complex
Overview
Group I introns are catalytic RNAs capable of orchestrating two sequential phosphotransesterification reactions that result in self-splicing. To understand how the group I intron active site facilitates catalysis, we have solved the structure of an active ribozyme derived from the orf142-I2 intron from phage Twort bound to a four-nucleotide product RNA at a resolution of 3.6 A. In addition to the three conserved domains characteristic of all group I introns, the Twort ribozyme has peripheral insertions characteristic of phage introns. These elements form a ring that completely envelops the active site, where a snug pocket for guanosine is formed by a series of stacked base triples. The structure of the active site reveals three potential binding sites for catalytic metals, and invokes a role for the 2' hydroxyl of the guanosine substrate in organization of the active site for catalysis.
About this Structure
Full crystallographic information is available from OCA.
Reference
Crystal structure of a phage Twort group I ribozyme-product complex., Golden BL, Kim H, Chase E, Nat Struct Mol Biol. 2005 Jan;12(1):82-9. Epub 2004 Dec 5. PMID:15580277 Page seeded by OCA on Sat May 3 15:44:39 2008
