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Published on: August 9, 2011
Building of RNA and DNA double helices into electron density
Frantisek Pavelcik1, Bohdan Schneider
1Department of Chemical Drugs, Faculty of Pharmacy, University of Veterinary and Pharmaceutical Sciences in Brno, CZ-61242 Brno, Czech Republic. pavelcikf@vfu.cz
Abstract:
A method has been developed that automatically fits double-helical regions into the electron density of nucleic acid structures. Rigid fragments consisting of two Watson-Crick base pairs and three pairs of phosphate groups in the A-type or B-type conformation are positioned into the electron density by phased rotation and translation functions. The position and orientation of the localized double-helical fragments are determined by phased refinement. The method has been tested by building double-helical regions of nine RNA structures of variable crystallographic resolution and polynucleotide length and is available for free use.
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