Observation of Cleavage in DNA and Nucleotides Following Oxygen K-shell Ionization by Measuring X-ray Absorption Near Edge Structure.
Summary of "Observation of Cleavage in DNA and Nucleotides Following Oxygen K-shell Ionization by Measuring X-ray Absorption Near Edge Structure."
Abstract Purpose: To investigate which type of bond is more likely to be cleaved in functional groups in DNA including the nucleobases by the K-shell ionization of oxygen of DNA, and to determine whether the production of propenal is specific to the oxygen resonant excitation. To investigate the degradation pattern, which depends on the type of nucleobase in the DNA monomer. Materials and Methods: Calf thymus DNA film and four nucleotides (dAMP, TMP, dGMP, and dCMP) films were used as samples. Soft X-rays with energy of 560 eV were used to irradiate the samples, and the changes in the X-ray absorption near edge structure (XANES) spectra during the irradiation were measured. The XANES measurements were performed by using a 0.02 eV scanning photon energy step. Results: The difference spectra for DNA and nucleotides were similar to those for pyridine deprotonation. The oxygen K-edge regions in the difference spectra were all similar apart from for the spectrum obtained at the resonant excitation energy of oxygen in DNA. The spectral change did not depend on the type of nucleotide. Conclusion: (1) Deprotonation of the nucleobase -NH is usually induced by core ionization of carbon, nitrogen, and oxygen. (2) Propenal production is specific to the oxygen K-shell resonant excitation. (3) The pattern of XANES spectral changes does not significantly depend on the type of nucleobase.
Affiliation
Journal Details
This article was published in the following journal.
Name: International journal of radiation biology
ISSN: 1362-3095
Pages:
Links
- PubMed Source: http://www.ncbi.nlm.nih.gov/pubmed/22702534
- DOI: http://dx.doi.org/10.3109/09553002.2012.703363
Medical and Biotech [MESH] Definitions
Observation
The act of regarding attentively and studying facts and occurrences, gathering data through analyzing, measuring, and drawing conclusions, with the purpose of applying the observed information to theoretical assumptions. Observation as a scientific method in the acquisition of knowledge began in classical antiquity; in modern science and medicine its greatest application is facilitated by modern technology. Observation is one of the components of the research process.
Biological Oxygen Demand Analysis
Testing for the amount of biodegradable organic material in a water sample by measuring the quantity of oxygen consumed by biodegradation of those materials over a specific time period.
Dna Cleavage
A reaction that severs one of the covalent sugar-phosphate linkages between NUCLEOTIDES that compose the sugar phosphate backbone of DNA. It is catalyzed enzymatically, chemically or by radiation. Cleavage may be exonucleolytic - removing the end nucleotide, or endonucleolytic - splitting the strand in two.
Phosphorus-oxygen Lyases
Enzymes that catalyze the cleavage of a phosphorus-oxygen bond by means other than hydrolysis or oxidation. EC 4.6.
Carbon-oxygen Lyases
Enzymes that catalyze the cleavage of a carbon-oxygen bond by means other than hydrolysis or oxidation. EC 4.2.
PubMed Articles
The TiO2-polyaniline (PANI) core-shell nanofibers with unique ultraviolet (UV) photoresponse were designed and fabricated. When the core-shell nanofibers were tested in an oxygen (O2) and a non-oxygen...
Core-shell effects in the ionization of doped helium nanodroplets.
Core-shell particles with water clusters as the core and surrounded by an atomic or molecular shell have been synthesized for the first time by adding water and a co-dopant sequentially to helium nano...
The aim of this study was to establish a simultaneous quantitative analysis method of nine endogenous nucleotides in rat plasma using micellar electrokinetic capillary chromatography/electrospray ioni...
Photoionization of Yb(NH3 )n Complexes.
The ionization energies of complexes between a rare-earth metal (Yb) and ammonia were measured for the first time. Using photoionization mass spectrometry under molecular-beam conditions, the adiabati...
The observation of gaseous gold superions induced from monodispersed nanoparticles.
Gold cluster ions: Au(17) (-) and Au(19) (+) were identified by MALDI-ToF MS from Au(19) (SC(2) H(4) )(13) (for Au(17) (-) , see figure). Both have an 18-electro...
Clinical Trials
Tritanium® Primary Acetabular Shell Study
This study will be a prospective, non-randomized evaluation of the Tritanium® Primary Acetabular Shell for primary total hip replacement (THR) with a cementless application in a consecuti...
Clinical Effects of a Nucleotides-Supplemented Infant Formula
The study hypothesis is that different concentrations of nucleotides' supplementation of an infant formula might affect differently growth and/or other clinical parameters in neonates.
Trident® Tritanium™ Acetabular Shell Revision Study
The purpose of this study is to evaluate a hip implant system used when a previous hip replacement surgery has failed.
Doxorubicin or Epirubicin and Cyclophosphamide in Treating Older Women With Invasive Breast Cancer
RATIONALE: Drugs used in chemotherapy, such as doxorubicin, epirubicin, and cyclophosphamide, work in different ways to stop the growth of tumor cells, either by killing the cells or by st...
Imaging and Biomarkers of Hypoxia in Solid Tumors
To establish PET imaging with the tracer FMISO as an accurate and reliable method for measuring the oxygen content of a tumor and to establish the measurement of secreted markers in blood...
