1hmh
From Proteopedia
THREE-DIMENSIONAL STRUCTURE OF A HAMMERHEAD RIBOZYME
Overview
The hammerhead ribozyme is a small catalytic RNA motif made up of three base-paired stems and a core of highly conserved, non-complementary nucleotides essential for catalysis. The X-ray crystallographic structure of a hammerhead RNA-DNA ribozyme-inhibitor complex at 2.6 A resolution reveals that the base-paired stems are A-form helices and that the core has two structural domains. The first domain is formed by the sequence 5'-CUGA following stem I and is a sharp turn identical to the uridine turn of transfer RNA, whereas the second is a non-Watson-Crick three-base-pair duplex with a divalent-ion binding site. The phosphodiester backbone of the DNA inhibitor strand is splayed out at the phosphate 5' to the cleavage site. The structure indicates that the ribozyme may destabilize a substrate strand in order to facilitate twisting of the substrate to allow cleavage of the scissile bond.
About this Structure
Full crystallographic information is available from OCA.
Reference
Three-dimensional structure of a hammerhead ribozyme., Pley HW, Flaherty KM, McKay DB, Nature. 1994 Nov 3;372(6501):68-74. PMID:7969422 Page seeded by OCA on Fri May 2 19:00:55 2008
