THE CD OF LIGAND-DNA SYSTEMS .2. POLY(DA-DT) B-DNA
Journal article, 1992

A systematic theoretical study of the CD of [poly (dA-dT)]2 and its complexes with achiral small molecules is presented. The CD spectra of [poly (dA-dT)]2 and of poly (dA):poly(dT) are calculated for various DNA structures using the matrix method. The calculated and experimental spectra agree reasonably well for [poly(dA-dT)]2 but less well for poly(dA):poly(dT). The calculated CD spectrum of [poly(dA-dT)]2 fails to reproduce the wavelength region of 205-245 nm of the experimental spectrum. This discrepancy can be explained by a magnetic dipole allowed transition contributing significantly to the CD spectrum in this region. The induced CD of a transition moment of a molecule bound to [poly(dA-dT)]2 is also calculated. As was the case for [poly(dG-dC)]2, the induced CD of a groove bound molecule is one order of magnitude stronger than that of an intercalated molecule. The calculations also show considerable differences between pyrimidine-purine sites and purine-pyrimidine sites. Both signs and magnitudes of the CD induced into ligands bound in the minor groove agree with experimental observations.

9-ethylguanine

adenine chromophore

parameters

linear dichroism

nucleic-acid monomers

transition

complexes

induced circular-dichroism

netropsin

electronic-spectrum

Author

Reidar Lyng

Department of Physical Chemistry

A. Rodger

Bengt Nordén

Department of Physical Chemistry

Biopolymers

0006-3525 (ISSN) 1097-0282 (eISSN)

Vol. 32 9 1201-1214

Subject Categories

Biochemistry and Molecular Biology

DOI

10.1002/bip.360320910

More information

Created

10/6/2017