Why do DNA helical models exhibit wedge rolls? A mathematical rationale

Bhattacharyya, Dhananjay and Bansal, Manju (1988) Why do DNA helical models exhibit wedge rolls? A mathematical rationale. In: Current Science, 57 (21). pp. 1159-1162.

PDF helicalfinal.pdf Download (282kB)

Abstract

The base-pair parameters wedge-tilt and wedge-roll are extremely useful for describing curved DNA structures. The wedge effect has generally been assumed to be due to the differences between the base-pair tilts and rolls of two successive base-pairs in a DNA molecule. A mathematical formalism has been established here, which shows that, wedgc-roll is a function of basepair tilt and helical twist, similarly the wedge-tilt is a function of base-pair roll and helical twist. This provides a straightforward explanation for the reported wedge-roll in A-DNA helical model of $12^0$ and gives a value of $-3.8^0$ for B-DNA fiber model. The wedge-rolls and wedgetilts calculated for the oligonucleotide crystal structures, using these relations, are in excellent agreement with the values reported earlier, which were .calculated directly from the coordinates, using a global helix axis.

Item Type:	Journal Article
Publication:	Current Science
Publisher:	Indian Academy of Science
Additional Information:	Copyright of this article belongs to Indian Academy of Science.
Department/Centre:	Division of Biological Sciences > Molecular Biophysics Unit
Date Deposited:	21 Feb 2008
Last Modified:	19 Sep 2010 04:42
URI:	http://eprints.iisc.ac.in/id/eprint/13074

Actions (login required)

View Item