The change of dna and protein radiation damage upon hydration: in-situ observations by near-ambient-pressure xps
- X-ray photoelectron-spectroscopy (XPS) allows simultaneous irradiation and damage monitoring. Although water radiolysis is essential for radiation damage, all previous XPS studies were performed in vacuum. Here we present near-ambient-pressure XPS experiments to directly measure DNA damage under water atmosphere. They permit in-situ monitoring of the effects of radicals on fully hydrated double-stranded DNA. Our results allow us to distinguish direct damage, by photons and secondary low-energy electrons (LEE), from damage by hydroxyl radicals or hydration induced modifications of damage pathways. The exposure of dry DNA to x-rays leads to strand-breaks at the sugar-phosphate backbone, while deoxyribose and nucleobases are less affected. In contrast, a strong increase of DNA damage is observed in water, where OH-radicals are produced. In consequence, base damage and base release become predominant, even though the number of strand-breaks increases further. Furthermore, first data aboutX-ray photoelectron-spectroscopy (XPS) allows simultaneous irradiation and damage monitoring. Although water radiolysis is essential for radiation damage, all previous XPS studies were performed in vacuum. Here we present near-ambient-pressure XPS experiments to directly measure DNA damage under water atmosphere. They permit in-situ monitoring of the effects of radicals on fully hydrated double-stranded DNA. Our results allow us to distinguish direct damage, by photons and secondary low-energy electrons (LEE), from damage by hydroxyl radicals or hydration induced modifications of damage pathways. The exposure of dry DNA to x-rays leads to strand-breaks at the sugar-phosphate backbone, while deoxyribose and nucleobases are less affected. In contrast, a strong increase of DNA damage is observed in water, where OH-radicals are produced. In consequence, base damage and base release become predominant, even though the number of strand-breaks increases further. Furthermore, first data about the degradation of single-stranded DNA binding-proteins (G5P / GV5 and hmtSSB) under vacuum and NAP-XPS conditions are presented.…
Autor*innen: | Marc Benjamin HahnORCiD |
---|---|
Koautor*innen: | P. M. Dietrich, Jörg RadnikORCiD, Tihomir Solomun, Dorothea C. Hallier, H. Seitz |
Dokumenttyp: | Vortrag |
Veröffentlichungsform: | Präsentation |
Sprache: | Englisch |
Jahr der Erstveröffentlichung: | 2023 |
Organisationseinheit der BAM: | 6 Materialchemie |
6 Materialchemie / 6.1 Oberflächen- und Dünnschichtanalyse | |
6 Materialchemie / 6.6 Physik und chemische Analytik der Polymere | |
DDC-Klassifikation: | Naturwissenschaften und Mathematik / Chemie / Analytische Chemie |
Freie Schlagwörter: | Base damage; Base loss; Cancer treatment; DEA; DET; DNA; DSB; Dosimetry; ESCA; G5P; GVP; Geant4; Geant4-DNA; Hydroxyl radical; LEE; Microdosimetry; NAP-XPS; Near ambient pressure xray photo electron spectroscopy; Prehydrated electron; Protein; Proteins; ROS; Radiation damage; Reactive oxygen species; SSB; Single-strand break (SSB); Single-stranded DNA-binding proteins; TOPAS; Xray photo electron spectrocopy |
Themenfelder/Aktivitätsfelder der BAM: | Chemie und Prozesstechnik |
Veranstaltung: | AVS69 |
Veranstaltungsort: | Portland, USA |
Beginndatum der Veranstaltung: | 05.11.2023 |
Enddatum der Veranstaltung: | 10.11.2023 |
Zugehöriger Identifikator: | https://doi.org/10.1038/s42004-021-00487-1 |
Verfügbarkeit des Dokuments: | Datei im Netzwerk der BAM verfügbar ("Closed Access") |
Datum der Freischaltung: | 07.11.2023 |
Referierte Publikation: | Nein |
Eingeladener Vortrag: | Nein |