A5066921715- Advanced NMR Techniques and Applications
- Lipid Membrane Structure and Behavior
- Medical Imaging Techniques and Applications
- Advanced X-ray and CT Imaging
- Supramolecular Self-Assembly in Materials
- Solid-state spectroscopy and crystallography
- Protein Structure and Dynamics
- Photoreceptor and optogenetics research
- Electron Spin Resonance Studies
- Nuclear Physics and Applications
- Advanced MRI Techniques and Applications
- Digital Radiography and Breast Imaging
- Advanced X-ray Imaging Techniques
- Crystallization and Solubility Studies
- Molecular spectroscopy and chirality
- X-ray Diffraction in Crystallography
- NMR spectroscopy and applications
- Radiation Dose and Imaging
- Advanced Radiotherapy Techniques
- Biochemical effects in animals
- Transition Metal Oxide Nanomaterials
- Atomic and Subatomic Physics Research
- Muon and positron interactions and applications
- Photoacoustic and Ultrasonic Imaging
- Biopolymer Synthesis and Applications
Institute for Molecular Science
2013-2025
The Graduate University for Advanced Studies, SOKENDAI
2012-2025
National Institutes of Natural Sciences
2006-2023
Ibaraki Prefectural University of Health Sciences
1996-2009
University of Hyogo
2007-2009
Yokohama National University
2003-2008
Hiroshima University
2007
University of Toyama
2006
San Francisco State University
2005
Florida State University
2000-2002
Covalent organic frameworks are a class of crystalline porous polymers that integrate molecular building blocks into periodic structures and usually synthesized using two-component [1+1] condensation systems comprised one knot linker. Here we report general strategy based on multiple-component [1+2] [1+3] enable the use two or three linker units for synthesis hexagonal tetragonal covalent frameworks. Unlike systems, feature asymmetric tiling anisotropic skeletons unusually shaped pores. This...
The heart of the H+ conductance mechanism in homotetrameric M2 channel from influenza A is a set four histidine side chains. Here, we show that protonation third these imidazoles coincides with acid activation this transmembrane and that, at physiological pH, closed by two imidazole-imidazolium dimers, each sharing low-barrier hydrogen bond. This unique construct succeeds distributing pair charges over rings many atoms low dielectric environment to minimize charge repulsion. These dimers...
An interhelical distance has been precisely measured by REDOR solid-state NMR spectroscopy in the transmembrane tetrameric bundle of M2-TMP, from M2 proton channel influenza A viral coat. The high-resolution structure helical backbone determined using orientational restraints uniformly aligned peptide preparations hydrated dimyristoylphosphatidylcholine bilayers. Here, between (15)N(pi) labeled His37 and (13)C(gamma) Trp41 is to be less than 3.9 A. Such a short distance, combination with...
The synthesis and characterization of fused aromatic networks composed zinc tetrapyrazinoporphyrazines are reported. steric repulsion bulky substituents induced the formation three-dimensional structures. Thus-obtained insoluble polymers adsorbed...
We have previously suggested that crystalline Bombyx mori silk in II form (the structure after spinning) is not a simple antiparallel β-sheet but intrinsically heterogeneous. Using the peptide (AG)15, we obtained first fully assigned high resolution solid state 1H NMR spectrum. Distinct heterogeneity was observed, both and 13C CP/MAS signals. Based on these results, new model proposed contains two different packing arrangements of β-sheets. The structures were energetically minimized by...
New acid/base-responsive organic compounds were discovered to undergo electron transfer disproportionation.
Alzheimer's disease (AD) is associated with progressive accumulation of amyloid-β (Aβ) cross-β fibrils in the brain. Aβ species tightly GM1 ganglioside, a glycosphingolipid abundant neuronal membranes, promote amyloid fibril formation; therefore, they could be attractive clinical targets. However, active conformational state GM1-containing lipid membranes still unknown. The present solid-state nuclear magnetic resonance study revealed nonfibrillar assemblage characterized by double-layered...
Examination of 1,625 Japanese patients with keratoconus and 20 pellucid marginal corneal degeneration showed that 17 also had in the central portion cornea. Three without bilateral involvement. Among cases keratoconus, eight involvement others unilateral Pellucid or may be a variant different manifestation same etiologic factor.
The accurate 1H positions of alanine-glycine alternating copolypeptide, (AG)15 with Silk I structure were determined. For the purpose, geometry optimization was performed starting atomic coordinates hetero atoms reported previously (Macromolecules 2005, 38, 7397−7403) and applied only for protons under periodic boundary conditions. agreement between calculated observed chemical shifts all 1H,13C 15N nuclei excellent, indicating strongly that determination atomic-coordinate including high...
Abstract A one‐handed 3 10 ‐helical hexapeptide is efficiently encapsulated within the helical cavity of st‐PMMA when a fullerene (C 60 ) derivative introduced at C‐terminal end peptide. The encapsulation accompanied by induction preferred‐handed conformation in backbone with same‐handedness as that to form crystalline st‐PMMA/peptide‐C inclusion complex unique optically active helix‐in‐helix structure. Although unable encapsulate peptide without terminal C unit, hollow space almost filled...
The interatomic distances in the crystalline specimen of 13C,15N doubly labeled peptides [1-13C]N-acetyl-Pro-[15N]Gly-Phe (I), N-acetyl-[1-13C]Pro-Gly-[15N]Phe (II), and [1-13C]N-acetyl-Pro-Gly-[15N]Phe (III) evaluated from rotational echo double resonance (REDOR) data were compared with those X-ray diffraction studies justify our novel approach. minimization B1 inhomogeneity was critical to obtain accurate distances, which achieved by confinement samples central portion (50% total filling...
The transitional process in the Cu 3 Au alloy from disordered to ordered state and relaxation phase change have been investigated by measuring time dependence of X-ray superstructure line width electrical resistivity. is realized a rapid sample temperature comparison with this process. average cluster size increases proportion t 1/2 irrespective ageing temperature. This compared theoretical result Kawasaki et al. distribution function clusters obtained shape. We observe two kinds times τ D→0...
Bovine lactoferrampin (LFampinB) is a newly discovered antimicrobial peptide found in the N1-domain of bovine lactoferrin (268–284), and consists 17 amino-acid residues. It important to determine orientation structure LFampinB bacterial membranes reveal mechanism. We therefore performed 13C 31P NMR, 13C-31P rotational echo double resonance (REDOR), potassium ion-selective electrode, quartz-crystal microbalance measurements for with mimetic membrane molecular-dynamics simulation acidic...
Alanine oligomers provide a key structure for silk fibers from spider and wild silkworms.We report on structural analysis of L-alanyl-L-alanyl-L-alanyl-L-alanine (Ala)4 with anti-parallel (AP) β-structures using X-ray solid-state NMR. All the Ala residues in are equivalent positions, whereas alanine trimer (Ala)3 there two alternative locations unit cell as reported previously (Fawcett Camerman, Acta Cryst., 1975, 31, 658-665). AP β-structure is more stable than AP-(Ala)3 due to formation...
The accurate 1H positions of alanine tripeptide, A3, with anti-parallel and parallel β-sheet structures could be determined by highly resolved DQMAS solid-state NMR spectra chemical shift calculation gauge-including projector augmented wave calculations.
Backbone conformations near tyrosine in bacteriorhodopsin (bR) corresponding to all-trans and 13-cis retinal configurations the dark, light, pressure adapted states were investigated for Tyr-X peptide bonds by using double amino acid labeling with [1-13C]Tyr, [15N]X-bR means of rotational echo resonance (REDOR) technique. The NMR signals obtained from difference spectra between REDOR full experiments allowed selectively detect on a Tyr185-Pro186, Tyr26-Phe27, Tyr64-Gly65. Two 13C peaks...
Bacteriorhodopsin (bR) is a retinal protein in purple membrane of Halobacterium salinarum, which functions as light-driven proton pump. We have detected pressure-induced isomerization bR by analyzing 15N cross polarization-magic angle spinning (CP-MAS) NMR spectra [zeta-15N]Lys-labeled bR. In the 15N-NMR spectra, both all-trans and 13-cis configurations been observed Lys N(zeta) protonated Schiff base at 148.0 155.0 ppm, respectively, MAS frequency 4 kHz dark. When was increased up to 12...