A5062331266- DNA Repair Mechanisms
- DNA and Nucleic Acid Chemistry
- Protein Structure and Dynamics
- Enzyme Structure and Function
- Electron and X-Ray Spectroscopy Techniques
- Genomics and Chromatin Dynamics
- Porphyrin and Phthalocyanine Chemistry
- Photosynthetic Processes and Mechanisms
- Origins and Evolution of Life
- Semiconductor materials and devices
- Oxidative Organic Chemistry Reactions
- Epigenetics and DNA Methylation
- Spectroscopy and Quantum Chemical Studies
- Silicon Carbide Semiconductor Technologies
- Carbon Nanotubes in Composites
- Advanced Chemical Physics Studies
- Plant Genetic and Mutation Studies
- Graphene research and applications
- Mass Spectrometry Techniques and Applications
- Semiconductor materials and interfaces
- Photoreceptor and optogenetics research
- Molecular spectroscopy and chirality
- Photochromic and Fluorescence Chemistry
- Astro and Planetary Science
- Carcinogens and Genotoxicity Assessment
National Institutes for Quantum Science and Technology
2022-2024
Hiroshima University
2016-2021
Kobe University
2008-2020
Japan Synchrotron Radiation Research Institute
2012-2017
Osaka University
2003-2017
Nara Institute of Science and Technology
2017
Japan Atomic Energy Agency
1968-2016
Advanced Science Research Center
2014-2015
SPring-8
2012-2014
Japan Society for the Promotion of Science
2009-2011
Deployments of spherical grids to obtain high energy and angular resolutions for retarding field analyzers (RFAs) having acceptance angles as large or larger than ±45° were explored under the condition using commercially available microchannel plates with effective diameters approximately 100 mm. As a result electron trajectory simulations, deployment three significantly different grid separations instead conventional equidistant showed an resolving power (E/ΔE) 3200 resolution 0.6°. The...
We investigated the electronic and local crystal structures of sintered half-Heusler ZrNiSn alloy by synchrotron radiation photoemission spectroscopy (SR-PES), X-ray powder diffraction (SR-XRD) measurements, band structure calculations to clarify mechanisms leading improvements in thermoelectric properties materials. In contrast predicted semiconductor-like structure, SR-PES results show a pseudo-gap at Fermi level, SR-XRD analysis reveals an interstitial Ni disorder structure. An...
We use core level and valence band soft x-ray photoemission spectroscopy (SXPES) to investigate electronic structure of new BiS$_{2}$ layered superconductor LaO$_{1-x}$F$_{x}$BiS$_{2}$. Core spectra doped samples show a spectral feature at the lower binding energy side Bi 4${f}$ main peak, which may be explained by core-hole screening with metallic states near Fermi ($E_{\rm F}$). Experimental its ${x}$ dependence (higher shift as well appearance $E_{\rm F}$ having dominant 6${p}$ character)...
Circular dichroism (CD) spectroscopy in the soft x-ray energy region is a new tool to study local structure of chiral materials. In this paper, we introduce method measure high-quality CD spectra oxygen K-edge region. Characteristic thin films amino acids L-tyrosine and L-aspartic acid are reported compared with those L-alanine L-serine. The signals from 1s → π* transitions COO−, which common moiety these acids, reflect geometry each acid.
We report the global structural alterations in histone H3 proteins induced by lysine-9 mono-, di- and trimethylation, which are part of critical post-translational modifications for DNA damage responses, identified using synchrotron radiation circular dichroism (CD) spectroscopy. Compared with unmodified H3, mono- dimethylation increases number α-helices decreases numbers β-strands, while trimethylation α-helix content β-strand content. Comparison secondary-structure contents these suggests...
Soft X-ray natural circular dichroism (SXNCD) spectra of serine (Ser) and alanine (Ala) thin films, were measured in absolute value with the focus at oxygen 1s → π* transition COO-. In case L-Ser, a positive negative SXNCD peaks observed around 531.5 532.5 eV, respectively. L-Ala, peak was 532.8 eV. The intensity L-Ala about ten times as large that L-Ser. Those differences would reflect chiral environment core hole atoms
Synchrotron-radiation circular-dichroism spectroscopy was used to reveal that the DNA damage response induces a decrement of α-helix and an increment β-strand contents histone H3-H4 extracted from X-ray-irradiated human HeLa cells. The trend structural alteration qualitatively opposite our previously reported results for H2A-H2B. These strongly suggest histones share roles in responses, particularly repair processes chromatin remodeling, via specific each histone.
Abstract We report structural alterations of histone H3 proteins induced by lysine‐4 (K4) monomethylation, dimethylation, and trimethylation identified using synchrotron radiation circular dichroism spectroscopy. Compared with unmethylated H3, monomethylation dimethylation increases in α‐helix structures decreases β‐strand structures. In contrast, decreased content but increased content. The differences among K4‐unmethylated/methylated may allow epigenetic enzymes to discriminate the...
The mechanism of the one-order-of-magnitude increase in density vertically aligned carbon nanotubes (CNTs) achieved by a recently developed thermal chemical vapor deposition process was studied using synchrotron radiation spectroscopic techniques. In process, Ti film is used as underlayer for an Fe catalyst film. A characteristic point this that C2H2 feeding starts at low temperature 450°C, whereas conventional temperatures are ∼800°C. Photoemission spectroscopy soft and hard X-rays revealed...
We measured and compared the circular dichroism (CD) spectra secondary structures of histone proteins H2A, H2B their variants extracted from X-irradiated unirradiated human HeLa cells. Compared to cells, a relative increase in α-helix structure decrease other was observed These structural alterations persisted for at least 24 h, which is substantially longer than 2 h generally known be required DNA double-strand break repair.
The 18.5-kDa isoform of myelin basic protein (MBP) interacts with the membrane surface sheath to construct its compact multilamellar structure. This study characterized conformation MBP in by measuring vacuum-ultraviolet circular-dichroism (VUVCD) spectra bilayer liposome comprising following essential lipid constituents sheath: phosphatidylinositol (PI), phosphatidylinositol-4-phosphate (PIP), and phosphatidylinositol-4,5-bisphosphate (PIP2). exhibited characteristic peaks helix structure...
To understand the mechanism underlying high radio-sensitisation of living cells possessing brominated genomic DNA, X-ray photoelectron spectroscopy was used to study and nonbrominated nucleobases, nucleosides nucleotides.
To experimentally investigate the role of hydration in initial process decomposition 2-deoxy-d-ribose (dR), which is a major component DNA backbone, we used mass spectrometry to monitor ions desorbing from hydrated dR films exposed monochromatic soft X rays (560 eV). The X-ray photons preferentially ionize K-shell electrons oxygen atoms DNA. Hydrated samples were prepared under vacuum by exposing cooled (∼150 K) film deposited on Si substrate water vapor. Using quadrupole spectrometer,...
With the increasing interest in scarce proteins, reducing sample volume for circular dichroism (CD) spectroscopy has become desirable. Demagnification of incident beam size is required to reduce CD detecting transmitted light passed through sample. In this study, was demagnified using a focal mirror, and small-capacity cells were developed an attempt volume. The original 6 × mm2; we successfully converged it 25 μm2 Schwarzschild objective (SO). new cell SO allowed be reduced 1/10 (15 → 1.5...
We investigated on the chemical bonding states of thermally oxidized SiO2/SiC in detail by angle-resolved X-ray photoemission spectroscopy (AR-XPS). Analyses Si 2p, C 1s and O1s spectra show that signal arising from sub-oxide is detected, signals related carbon SiO2 C-C SiC are detected. also characterized SiO2/4H-SiC Hard (HAX-PES) order to check depth profile oxide detail.