|
|||||
|
|
Hole Migration in Telomere-Based Oligonucleotide Anions and G-Quadruplexes |
|
| Authors: | Wen Li Edita Mjekiqi Wessel Douma Xin Wang Dr Oksana Kavatsyuk Prof Dr Ronnie Hoekstra Dr Jean-Christophe Poully Dr Thomas Schlathölter |
| Institution: | 1. Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747AG Groningen, The Netherlands;2. Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747AG Groningen, The Netherlands
University College Groningen, University of Groningen, Hoendiepskade 23/24, 9718 BG Groningen, The Netherlands;3. CIMAP laboratory UMR 6252, Université de Caen Normandie/CEA/CNRS/ENSICAEN, Bd Becquerel, 14070 CAEN Cedex 5, France |
| Abstract: | Vacuum ultraviolet photoionization of a gas-phase oligonucleotide anion leads to the formation of a valence hole. This hole migrates towards an energetically favorable site where it can weaken bonds and ultimately lead to bond cleavage. We have studied Vacuum UV photoionization of deprotonated oligonucleotides containing the human telomere sequence dTTAGGG and G-quadruplex structures consisting of four dTGGGGT single strands, stabilized by NH4+ counter ions. The oligonucleotide and G-quadruplex anions were confined in a radiofrequency ion trap, interfaced with a synchrotron beamline and the photofragmentation was studied using time-of-flight mass spectrometry. Oligonucleotide 12-mers containing the 5'-TTAGGG sequence were found to predominantly break in the GGG region, whereas no selective bond cleavage region was observed for the reversed 5'-GGGATT sequence. For G-quadruplex structures, fragmentation was quenched and mostly non-dissociative single and double electron removal was observed. |
| Keywords: | charge migration oligonucleotide photoionization synchrotron radiation telomere |