New parameters for the refinement of nucleic acid-containing structures

Autor: Axel T. Brunger, Gary N. Parkinson, Helen M. Berman, Jaroslav Vojtechovsky, L. Clowney
Rok vydání: 1996
Předmět:
Zdroj: Acta Crystallographica Section D Biological Crystallography. 52:57-64
ISSN: 0907-4449
DOI: 10.1107/s0907444995011115
Popis: Structures at atomic resolution (up to 1.0 A) which contain bases, sugars or the phosphodiester linkage, were selected from the Nucleic Acid Database or the Cambridge Structural Database to build a nucleic acid dictionary from X-ray refined structures. The dictionary consists of the average values for bond distances, bond angles and dihedral angles. The variance of the sample is used to provide information about the expected r.m.s. deviations of the refined parameters. A dictionary was constructed for refinement trials in X-PLOR. The dictionary includes RNA and DNA in C2'-endo and C3'-endo sugar pucker conformations, as well as values for the backbone dihedrals. Tests were performed on the dictionary using three structures: a B-DNA, a Z-DNA and a protein-DNA complex. During the course of refinement, all three structures showed significant improvements as measured by r.m.s. deviations and R factors when compared to the previous DNA dictionary.
Databáze: OpenAIRE