Premium
Intercalation of daunomycin into d(CG) 4 oligomer duplex containing G·T mismatches by vibrational circular dichroism and infrared absorption spectroscopy
Author(s) -
Pandyra A.,
Tsankov D.,
Andrushchenko V.,
van de Sande J. H.,
Wieser H.
Publication year - 2005
Publication title -
biopolymers
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.556
H-Index - 125
eISSN - 1097-0282
pISSN - 0006-3525
DOI - 10.1002/bip.20416
Subject(s) - chemistry , vibrational circular dichroism , infrared spectroscopy , histone octamer , crystallography , circular dichroism , absorption (acoustics) , infrared , spectroscopy , intercalation (chemistry) , stereochemistry , dna , optics , organic chemistry , biochemistry , physics , quantum mechanics , nucleosome , histone
The vibrational circular dichroism (VCD) and infrared absorption (IR) spectra of the mismatched octamer oligonucleotides d(CGTGCGCG) 2 ( CGT ) and d(CGCGTGCG) 2 ( CGC ) and their complexes with the antitumor drug daunomycin were measured in D 2 O, interpreted, and compared to the octamer d(CGCGCGCG) 2 ( CG ). The IR spectra of the mismatched octamers in the carbonyl‐stretching region are similar to those of the parent CG, whereas the VCD spectra differ in several respects between each other. The main VCD feature due to carbonyl stretching is informative for the mismatches and CG . Vibrational modes in the sugar–phosphate region remain essentially unchanged especially for PO 2 − symmetric stretching. Differences between the free and complexed mismatch octamers occurred mainly in the carbonyl‐stretching region (1700–1600 cm −1 ). The absorption intensity of the CO peak of G is more prominent for CGC than CGT and resembles CG in this respect. The detailed composition of this doublet is clearly visible, indicating the geometric rearrangement of the base pairs in the presence of the mismatch and upon forming the daunomycin complex. © 2005 Wiley Periodicals, Inc. Biopolymers 82: 189–198, 2006 This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com