Dissociative electron attachment to abasic DNA.
Thin films of the short single DNA strand, GCAT, in which one of the bases has been removed were bombarded with 3 to 15 eV electrons. The yield functions of the H(-), O(-) and OH(-) ions desorbed from these films exhibit a broad peak near 9 eV, which is attributed to dissociative electron attachment to the basic molecules. Whereas removal of any one of the bases considerably decreases N-glycosidic and backbone C-O bond scission, the creation of basic sites does not appreciably modify bond rupture leading to anion electron stimulated desorption. These seemingly contradictory results make it possible to propose a detailed mechanism leading to the transfer of electrons in the range 5-13 eV within DNA.
Ptasińska
Sylwia
S
Groupe en Sciences des Radiations, Faculté de Médecine, Université de Sherbrooke, Sherbrooke, QC, Canada J1H 5N4. sylwia.ptasinska@usherbrooke.ca
Sanche
Léon
L
D000838:Anions / Q000032:analysis; D001610:Beta Particles; D004247:DNA / Q000737:chemistry* / Q000528:radiation effects; D004583:Electrons; D015394:Molecular Structure
D000838:Anions; D004247:DNA