379d
From Proteopedia
THE STRUCTURAL BASIS OF HAMMERHEAD RIBOZYME SELF-CLEAVAGE
Overview
We have captured an 8.7 A conformational change that takes place in the cleavage site of the hammerhead ribozyme during self-cleavage, using X-ray crystallography combined with physical and chemical trapping techniques. This rearrangement brings the hammerhead ribozyme from the ground state into a conformation that is poised to form the transition state geometry required for hammerhead RNA self-cleavage. Use of a 5'-C-methylated ribose adjacent to the cleavage site permits this ordinarily transient conformational change to be kinetically trapped and observed crystallographically after initiating the hammerhead ribozyme reaction in the crystal. Cleavage of the corresponding unmodified hammerhead ribozyme in the crystal under otherwise identical conditions is faster than in solution, indicating that we have indeed trapped a catalytically relevant intermediate form of this RNA enzyme.
About this Structure
Full crystallographic information is available from OCA.
Reference
The structural basis of hammerhead ribozyme self-cleavage., Murray JB, Terwey DP, Maloney L, Karpeisky A, Usman N, Beigelman L, Scott WG, Cell. 1998 Mar 6;92(5):665-73. PMID:9506521 Page seeded by OCA on Sun May 4 20:17:59 2008
