title: Using DNA origami nanostructures to determine absolute cross sections for UV photon-induced DNA strand breakage.
abstract: We have characterized ultraviolet (UV) photon-induced DNA strand break processes by determination of absolute cross sections for photoabsorption and for sequence-specific DNA single strand breakage induced by photons in an energy range from 6.50 to 8.94 eV. These represent the lowest-energy photons able to induce DNA strand breaks. Oligonucleotide targets are immobilized on a UV transparent substrate in controlled quantities through attachment to DNA origami templates. Photon-induced dissociation of single DNA strands is visualized and quantified using atomic force microscopy. The obtained quantum yields for strand breakage vary between 0.06 and 0.5, indicating highly efficient DNA strand breakage by UV photons, which is clearly dependent on the photon energy. Above the ionization threshold strand breakage becomes clearly the dominant form of DNA radiation damage, which is then also dependent on the nucleotide sequence.
authors.affiliation: Institute of Chemistry, University of Potsdam , Karl-Liebknecht-Str. 24-25, 14469 Potsdam, Germany.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Vogel
authors.affiliation: Institute of Chemistry, University of Potsdam , Karl-Liebknecht-Str. 24-25, 14469 Potsdam, Germany.
authors.forename: Jenny
authors.initials: J
authors.lastname: Rackwitz
authors.affiliation: Institute of Chemistry, University of Potsdam , Karl-Liebknecht-Str. 24-25, 14469 Potsdam, Germany.|BAM Federal Institute for Materials Research and Testing , Richard-Willstätter Str. 11, 12489 Berlin, Germany.
authors.forename: Robin
authors.initials: R
authors.lastname: Schürman
authors.affiliation: Institute of Chemistry, University of Potsdam , Karl-Liebknecht-Str. 24-25, 14469 Potsdam, Germany.
authors.forename: Julia
authors.initials: J
authors.lastname: Prinz
authors.affiliation: Institute of Physics Belgrade, University of Belgrade , Pregrevica 118, 11080 Belgrade, Serbia.
authors.forename: Aleksandar R
authors.initials: AR
authors.lastname: Milosavljević
authors.affiliation: Synchrotron SOLEIL , 91192 Gif-sur-Yvette, France.
authors.forename: Matthieu
authors.initials: M
authors.lastname: Réfrégiers
authors.affiliation: Synchrotron SOLEIL , 91192 Gif-sur-Yvette, France.|UAR 1008 CEPIA, INRA, 44316 Nantes, France.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Giuliani
authors.affiliation: Institute of Chemistry, University of Potsdam , Karl-Liebknecht-Str. 24-25, 14469 Potsdam, Germany.|BAM Federal Institute for Materials Research and Testing , Richard-Willstätter Str. 11, 12489 Berlin, Germany.
authors.forename: Ilko
authors.initials: I
authors.lastname: Bald
mesh_terms: D004247:DNA / Q000737:chemistry*; D004249:DNA Damage / Q000528:radiation effects*; D004277:DNA, Single-Stranded / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D049329:Nanostructures / Q000737:chemistry*; D017785:Photons; D014466:Ultraviolet Rays
chemical_list: D004277:DNA, Single-Stranded; D004247:DNA
keywords: AFM; DNA; DNA origami; DNA radiation damage; UV radiation; cross sections for strand breakage