DSSR-PyMOL cartoon-block schematics: PDB entry 1kbd

PDB-id

1kbd; DSSR-derived features in text and JSON formats

Class

DNA

Method

NMR

Summary

Solution structure of a 16 base-pair DNA related to the hiv-1 kappa b site

Reference

Tisne C, Hantz E, Hartmann B, Delepierre M (1998): "Solution structure of a non-palindromic 16 base-pair DNA related to the HIV-1 kappa B site: evidence for BI-BII equilibrium inducing a global dynamic curvature of the duplex." J.Mol.Biol., 279, 127-142. doi: 10.1006/jmbi.1998.1757.

Abstract

1H and 31P NMR spectroscopy have been used together with molecular modelling to determine the fine structure of a non-palindromic 16 bp DNA containing the NF-kappa B binding site. Much emphasis has been placed upon NMR optimization of both two-dimensional 31P NMR techniques to extract structural information defining the phosphodiester backbone conformation and selective homonuclear 2D COSY experiments to determine sugar conformations. NMR data show evidence for a dynamic behaviour of steps flanking the ten base-pairs of the NF-kappa B binding site. A BI-BII equilibrium at these steps is demonstrated and two models for each extreme conformation are proposed in agreement with NMR data. In the refined BII structures, the NF-kappa B binding site exhibits an intrinsic curvature towards the major groove that is magnified by the four flanking steps in the BII conformation. Furthermore, the base-pairs are translated into the major groove. Thus, we present a novel mode of dynamic intrinsic curvature compatible with the DNA curvature observed in the X-ray structure of the p50-DNA complex.