A novel setup for the determination of absolute cross sections for low-energy electron induced strand breaks in oligonucleotides – The effect of the radiosensitizer 5-fluorouracil*

Rackwitz, Jenny; Ranković, Miloš Lj.; Milosavljević, Aleksandar R.; Bald, Ilko

doi:10.1140/epjd/e2016-70608-4

Cited by 25 publications

(35 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Thus, by recording the fluence dependence of N SB , the absolute cross section for strand breakage σ SB can be determined from the slope of the linear fit in the low‐fluence regime. For some of the sequences investigated here a relative method was used, in which one sequence with a known strand break cross section was used as a reference . The advantage of the relative method is that the absolute strand break cross section can be determined without recording a full fluence dependence of N SB …”

Section: Methodsmentioning

confidence: 99%

Low‐Energy Electron‐Induced Strand Breaks in Telomere‐Derived DNA Sequences—Influence of DNA Sequence and Topology

Rackwitz

Bald

2018

Chemistry A European J

Self Cite

View full text Add to dashboard Cite

During cancer radiation therapy high-energy radiation is used to reduce tumour tissue. The irradiation produces a shower of secondary low-energy (<20 eV) electrons, which are able to damage DNA very efficiently by dissociative electron attachment. Recently, it was suggested that low-energy electron-induced DNA strand breaks strongly depend on the specific DNA sequence with a high sensitivity of G-rich sequences. Here, we use DNA origami platforms to expose G-rich telomere sequences to low-energy (8.8 eV) electrons to determine absolute cross sections for strand breakage and to study the influence of sequence modifications and topology of telomeric DNA on the strand breakage. We find that the telomeric DNA 5'-(TTA GGG) is more sensitive to low-energy electrons than an intermixed sequence 5'-(TGT GTG A) confirming the unique electronic properties resulting from G-stacking. With increasing length of the oligonucleotide (i.e., going from 5'-(GGG ATT) to 5'-(GGG ATT) ), both the variety of topology and the electron-induced strand break cross sections increase. Addition of K ions decreases the strand break cross section for all sequences that are able to fold G-quadruplexes or G-intermediates, whereas the strand break cross section for the intermixed sequence remains unchanged. These results indicate that telomeric DNA is rather sensitive towards low-energy electron-induced strand breakage suggesting significant telomere shortening that can also occur during cancer radiation therapy.

show abstract

Section: Methodsmentioning

confidence: 99%

Low‐Energy Electron‐Induced Strand Breaks in Telomere‐Derived DNA Sequences—Influence of DNA Sequence and Topology

Rackwitz

Bald

2018

Chemistry A European J

Self Cite

View full text Add to dashboard Cite

show abstract

“…Using this technique, oligonucleotides (with and without radiosensitizers) were supported on a DNA origami triangle and irradiated with 10 eV electrons. Thereafter, the cross sections of damage were determined based on the analysis of atomic force microscopic images [3].In addition toŚmia lek's summary of the current state of our understanding of DNA damage [7], other contributed articles reported recent experimental results for other biologically-important molecules, primarily amino …”

mentioning

confidence: 99%

“…-low-energy interactions of charged particles (electrons [1][2][3][4][5][6][7], protons [8], positrons [9]), and photons [10] with atoms and molecules of biological [1][2][3][4]7,8], astrochemical [10], industrial, and environmental [5,6,9] interest; -molecular evolution of astrochemical ices [11][12][13]; -planetary atmospheric physics [14]; -atmospheric pressure photoionization and fragmentation of organic and inorganic aerosols [15]; -processes and applications of atmospheric pressure plasmas in astrochemical [16,17] and biomedical fields [17,18].…”

mentioning

confidence: 99%

“…In her colloquium paper,Śmia lek also discussed experimental issues and challenges experienced in the precise estimation of cross sections for DNA damage [7]. Similarly, in another contributed article, Rackwitz et al discussed the difficulties in establishing a reliable cross section for DNA damage, particularly strand breaks [3]. To overcome these challenges, the authors proposed a novel method to quantify absolute cross sections of strand breaks that low-energy electrons induce in oligonucleotides (synthesized, single-stranded DNA).…”

mentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Low-energy interactions related to atmospheric and extreme conditions

et al. 2017

Self Cite

View full text Add to dashboard Cite

This Topical Issue, entitled "Low-Energy Interactions Related to Atmospheric and Extreme Conditions", showcases a collection of eighteen articles that reported recent theoretical and experimental findings pertaining to the following topics:-low-energy interactions of charged particles (electrons [1-7] The contributed articles revealed that, in recent years, processes involving any kind of low-energy projectile (below a few keV) over a wide range of conditions have been recognized as important to many interdisciplinary research areas that span both the fundamental and applied sciences. For example, many studies on the topic of low-energy interactions (LEIs) have focused on probing gas or condensed phases under high-vacuum conditions. These studies model processes that can occur under physiological, industrial, atmospheric, or extreme conditions, the latter of which represent those that experience high levels of radiation in space. Therefore, this issue focuses on the most recent advances in the field of lowenergy processes, both at the fundamental and applied levels of elementary processes, and provides a state-of-theart description of current developments and discoveries. What follows is a brief summary of the most important conclusions derived from the collective findings. Over the last two decades, many LEI studies have focused on isolated biomolecules in the gas and condensed phases to understand and predict more accurately the reaction pathways and detailed mechanisms of damage to cellular components, such as DNA and proteins. In this issue,Śmia lek summarized and highlighted the pioneering work, together with the most prominent findings about DNA damage from an atomic and molecular physics perspective; this timely discussion contributes to a deeper understanding of the fundamental processes in cellular systems [7]. In her colloquium paper,Śmia lek also discussed experimental issues and challenges experienced in the precise estimation of cross sections for DNA damage [7]. Similarly, in another contributed article, Rackwitz et al. discussed the difficulties in establishing a reliable cross section for DNA damage, particularly strand breaks [3]. To overcome these challenges, the authors proposed a novel method to quantify absolute cross sections of strand breaks that low-energy electrons induce in oligonucleotides (synthesized, single-stranded DNA). Using this technique, oligonucleotides (with and without radiosensitizers) were supported on a DNA origami triangle and irradiated with 10 eV electrons. Thereafter, the cross sections of damage were determined based on the analysis of atomic force microscopic images [3].In addition toŚmia lek's summary of the current state of our understanding of DNA damage [7], other contributed articles reported recent experimental results for other biologically-important molecules, primarily amino

show abstract

Resonante Bildung von Strangbrüchen in sensibilisierten Oligonukleotiden induziert durch niederenergetische Elektronen (0.5–9.0 eV)

et al. 2017

Self Cite

View full text Add to dashboard Cite

In der Krebs-Strahlentherapie werden halogenierte Nukleinbasen als Radiosensibilisatoren eingesetzt, um die Reaktivitätd er DNAg egenüber niederenergetischen Elektronen (NEEs) zu erhçhen. NEEs erzeugen DNA-Strangbrüche bei spezifischen Energien (Resonanzen) durch dissoziative Elektronenanlagerung (DEA). Obwohl halogenierte Nukleinbasen intensive DEA-Resonanzen bei verschiedenen Elektronenenergien in der Gasphase aufweisen, kann der Einfluss der halogenierten Nukleinbasen auf tatsächliche DNA-Strangbrücheg rundsätzlichn ur schwer über den Energiebereich, in dem DEA stattfindet (< 12 eV), untersucht werden. Mithilfe von DNA-Origami-Nanostrukturen haben wir die Energieabhängigkeit der Wirkungsquerschnitte fürD NA-Strangbrüchev on Oligonukleotiden bestimmt, die mit 8-Bromadenin ( 8Br A) modifiziert wurden.D iese Ergebnisse wurden mit DEA-Messungen an isoliertem 8Br Ai nd er Gasphase verglichen. Entgegen der Erwartungen wird der Großteil der Strangbrüched urch Resonanzen um 7eVh ervorgerufen, wohingegen der Einfluss von Resonanzen bei sehr niedrigen Energien (< 2eV) auf die Strangbrüchegering ist.Abbildung 3. Massenspektren (negative Ionen) von gasfçrmigem 8Br A gekreuzt mit 0-eV-und 6-eV-Elektronen.Abbildung 4. Ionen-Ausbeuten der anionischen Fragmente mit 26, 65, 90 und 105 Da, aufgetragen als Funktion der Elektronenenergie.

show abstract

A novel setup for the determination of absolute cross sections for low-energy electron induced strand breaks in oligonucleotides – The effect of the radiosensitizer 5-fluorouracil*

Cited by 25 publications

References 38 publications

Low‐Energy Electron‐Induced Strand Breaks in Telomere‐Derived DNA Sequences—Influence of DNA Sequence and Topology

Low‐Energy Electron‐Induced Strand Breaks in Telomere‐Derived DNA Sequences—Influence of DNA Sequence and Topology

Low-energy interactions related to atmospheric and extreme conditions

Resonante Bildung von Strangbrüchen in sensibilisierten Oligonukleotiden induziert durch niederenergetische Elektronen (0.5–9.0 eV)

Contact Info

Product

Resources

About