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Bacillus halodurans RNase H catalytic domain mutant D132N in complex with 12-mer RNA/DNA hybridBacillus halodurans RNase H catalytic domain mutant D132N in complex with 12-mer RNA/DNA hybrid
Structural highlights
FunctionRNH1_HALH5 Endonuclease that specifically degrades the RNA of RNA-DNA hybrids.[1] Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedRNase H belongs to a nucleotidyl-transferase superfamily, which includes transposase, retroviral integrase, Holliday junction resolvase, and RISC nuclease Argonaute. We report the crystal structures of RNase H complexed with an RNA/DNA hybrid and a mechanism for substrate recognition and two-metal-ion-dependent catalysis. RNase H specifically recognizes the A form RNA strand and the B form DNA strand. Structure comparisons lead us to predict the catalytic residues of Argonaute and conclude that two-metal-ion catalysis is a general feature of the superfamily. In nucleases, the two metal ions are asymmetrically coordinated and have distinct roles in activating the nucleophile and stabilizing the transition state. In transposases, they are symmetrically coordinated and exchange roles to alternately activate a water and a 3'-OH for successive strand cleavage and transfer by a ping-pong mechanism. Crystal structures of RNase H bound to an RNA/DNA hybrid: substrate specificity and metal-dependent catalysis.,Nowotny M, Gaidamakov SA, Crouch RJ, Yang W Cell. 2005 Jul 1;121(7):1005-16. PMID:15989951[2] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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