Cooperative effects in the photophysical properties of self-associated triguanosine diphosphates.
The present study deals with the photophysical properties of triguanosine diphosphate in aqueous solutions, which are compared with those of the 2'-deoxyguanosine monophosphate. They are studied by steady-state absorption and fluorescence spectroscopy as well as by time-resolved fluorescence spectroscopy with femtosecond resolution. The temperature, salt and concentration dependence of the absorption and fluorescence spectra reveal that association of the trimers takes place. The resulting aggregates could correspond to a tetraplex structure. The aggregate fluorescence quantum yield is higher and the fluorescence lifetime much longer than those of the monomer. These results show the interaction between guanosine residues that may manifest itself via self-solvation, hydrogen bonding and/or delocalization of the excitation.
Laboratoire Francis Perrin, CEA/DSM/DRECAM/SPAM-CNRS URA 2453, Gif-sur-Yvette, France. dimitra.markovitsi@cea.fr
Dimitra
D
Markovitsi
Thomas
T
Gustavsson
Alexei
A
Sharonov
D003848:Deoxyguanine Nucleotides / Q000737:chemistry / Q000528:radiation effects; D005453:Fluorescence; D006153:Guanosine Diphosphate / Q000031:analogs & derivatives / Q000737:chemistry* / Q000528:radiation effects*; D006860:Hydrogen Bonding; D008027:Light; D015394:Molecular Structure; D010777:Photochemistry; D013050:Spectrometry, Fluorescence; D013696:Temperature; D014867:Water / Q000737:chemistry
D003848:Deoxyguanine Nucleotides; D014867:Water; C077233:2'-deoxyguanylic acid; D006153:Guanosine Diphosphate