Microhydration Prevents Fragmentation of Uracil and Thymine by Low-Energy Electrons

Kód výsledku v IS VaVaI

RIV/61388955:_____/16:00461876 - isvavai.cz

Výsledek na webu

http://dx.doi.org/10.1021/acs.jpclett.6b01601

DOI - Digital Object Identifier

10.1021/acs.jpclett.6b01601

Jazyk výsledku

angličtina

Název v původním jazyce

Microhydration Prevents Fragmentation of Uracil and Thymine by Low-Energy Electrons

Popis výsledku v původním jazyce

When ionizing radiation passes biological matter, a large number of secondary electrons with very low energies (<3 eV) is produced. It is known that such electrons cause an efficient fragmentation of isolated nucleobases via dissociative electron attachment. We present an experimental study of the electron attachment to microhydrated nucleobases. Our novel approach allows significant control over the hydration of molecules studied in the molecular beam. We directly show for the first time that the presence of a few water molecules suppresses the dissociative channel and leads exclusively to formation of intact molecular and hydrated anions. The suppression of fragmentation is ascribed to caging-like effects and fast energy transfer to the solvent. This is in contrast with theoretical prediction that microhydration strongly enhances the fragmentation of nucleobases. The current observation impacts mechanisms of reductive DNA strand breaks proposed to date on the basis of gas-phase experiments.

Název v anglickém jazyce

Microhydration Prevents Fragmentation of Uracil and Thymine by Low-Energy Electrons

Popis výsledku anglicky

When ionizing radiation passes biological matter, a large number of secondary electrons with very low energies (<3 eV) is produced. It is known that such electrons cause an efficient fragmentation of isolated nucleobases via dissociative electron attachment. We present an experimental study of the electron attachment to microhydrated nucleobases. Our novel approach allows significant control over the hydration of molecules studied in the molecular beam. We directly show for the first time that the presence of a few water molecules suppresses the dissociative channel and leads exclusively to formation of intact molecular and hydrated anions. The suppression of fragmentation is ascribed to caging-like effects and fast energy transfer to the solvent. This is in contrast with theoretical prediction that microhydration strongly enhances the fragmentation of nucleobases. The current observation impacts mechanisms of reductive DNA strand breaks proposed to date on the basis of gas-phase experiments.

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

CF - Fyzikální chemie a teoretická chemie

OECD FORD obor

—

Projekt

GJ16-10995Y: Reakce organometalických komplexů relevantní pro léčbu rakoviny iontovým svazkem

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2016

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Physical Chemistry Letters

ISSN

1948-7185

e-ISSN

—

Svazek periodika

7

Číslo periodika v rámci svazku

AUG 2016

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

5

Strana od-do

3401-3405

Kód UT WoS článku

000382603300018

EID výsledku v databázi Scopus

2-s2.0-84984904340