Capturing hammerhead ribozyme structures in action by modulating general base catalysis. PLoS Biol 2008 Sep 30;6(9):e234
Date
10/07/2008Pubmed ID
18834200Pubmed Central ID
PMC2553840DOI
10.1371/journal.pbio.0060234Scopus ID
2-s2.0-54749153656 (requires institutional sign-in at Scopus site) 78 CitationsAbstract
We have obtained precatalytic (enzyme-substrate complex) and postcatalytic (enzyme-product complex) crystal structures of an active full-length hammerhead RNA that cleaves in the crystal. Using the natural satellite tobacco ringspot virus hammerhead RNA sequence, the self-cleavage reaction was modulated by substituting the general base of the ribozyme, G12, with A12, a purine variant with a much lower pKa that does not significantly perturb the ribozyme's atomic structure. The active, but slowly cleaving, ribozyme thus permitted isolation of enzyme-substrate and enzyme-product complexes without modifying the nucleophile or leaving group of the cleavage reaction, nor any other aspect of the substrate. The predissociation enzyme-product complex structure reveals RNA and metal ion interactions potentially relevant to transition-state stabilization that are absent in precatalytic structures.
Author List
Chi YI, Martick M, Lares M, Kim R, Scott WG, Kim SHAuthor
Young-In Chi PhD Assistant Professor in the Surgery department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
Base SequenceCatalysis
Crystallography, X-Ray
Enzyme Stability
Molecular Sequence Data
Molecular Structure
Nepovirus
Nucleic Acid Conformation
RNA, Catalytic
Substrate Specificity
