Premium
Molecular Recognition and Visual Detection of G‐Quadruplexes by a Dicarbocyanine Dye
Author(s) -
Karg Beatrice,
Funke Andrea,
Ficht Anna,
SieversEngler Adrian,
Lämmerhofer Michael,
Weisz Klaus
Publication year - 2015
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.201502118
Subject(s) - stacking , g quadruplex , dna , fluorescence , chemistry , tetrad , crystallography , biophysics , topology (electrical circuits) , biochemistry , biology , genetics , physics , mathematics , combinatorics , organic chemistry , quantum mechanics
The interactions of a dicarbocyanine dye 3,3′‐diethylthiadicarbocyanine, DiSC 2 (5) , with DNA G‐quadruplexes were studied by means of a combination of various spectroscopic techniques. Aggregation of excess dye as a result of its positive charge is promoted by the presence of the polyanionic quadruplex structure. Specific high‐affinity binding to the parallel quadruplex of the MYC promoter sequence involves stacking of DiSC 2 (5) on the external G‐tetrads; the 5′‐terminal tetrad is the favored binding site. Significant energy transfer between DNA and the dye in the UV spectral region is observed upon DiSC 2 (5) binding. The transfer efficiency strongly depends on the DNA secondary structure as well as on the G‐quadruplex topology. These photophysical features enable the selective detection of DNA quadruplexes through sensitized DiSC 2 (5) fluorescence in the visible region.