A5002874878- Advanced NMR Techniques and Applications
- Protein Structure and Dynamics
- Electron Spin Resonance Studies
- Solid-state spectroscopy and crystallography
- Prion Diseases and Protein Misfolding
- Advanced MRI Techniques and Applications
- NMR spectroscopy and applications
- DNA and Nucleic Acid Chemistry
- Supramolecular Self-Assembly in Materials
- Molecular spectroscopy and chirality
- Alzheimer's disease research and treatments
- Genomics and Chromatin Dynamics
- Enzyme Structure and Function
- Trace Elements in Health
- Mesoporous Materials and Catalysis
- Magnetism in coordination complexes
- Photoreceptor and optogenetics research
- Neuroscience and Neuropharmacology Research
- Muon and positron interactions and applications
- Analytical Chemistry and Chromatography
- Various Chemistry Research Topics
- Zeolite Catalysis and Synthesis
- RNA Research and Splicing
- Polydiacetylene-based materials and applications
- RNA and protein synthesis mechanisms
The Ohio State University
2015-2024
Massachusetts Institute of Technology
1998-2013
Bruker (United States)
2010
Case Western Reserve University
2010
Université Claude Bernard Lyon 1
2010
Centre National de la Recherche Scientifique
2010
National High Magnetic Field Laboratory
2010
Bridge University
2010
National Institute of Diabetes and Digestive and Kidney Diseases
2004-2005
National Institutes of Health
2004-2005
The cross-β amyloid form of peptides and proteins represents an archetypal widely accessible structure consisting ordered arrays β-sheet filaments. These complex aggregates have remarkable chemical physical properties, the conversion normally soluble functional forms into structures is linked to many debilitating human diseases, including several common age-related dementia. Despite their importance, however, fibrils proved be recalcitrant detailed structural analysis. By combining...
Amyloid fibrils are self-assembled filamentous structures associated with protein deposition conditions including Alzheimer's disease and the transmissible spongiform encephalopathies. Despite immense medical importance of amyloid fibrils, no atomic-resolution available for these materials, because intact insoluble do not form diffraction-quality 3D crystals. Here we report high-resolution structure a peptide fragment amyloidogenic transthyretin, TTR(105–115), in its fibrillar form,...
We describe a new fivefold symmetric approach to homonuclear recoupling in rotating solids that is based on rotor-synchronized, spin-lock rf irradiation of the type employed previously MELODRAMA and C7 (and their derivative sequences) for C13–13C recoupling. The sequence, like its sevenfold relatives, γ-encoded, therefore exhibits theoretical efficiency ∼73% double quantum filtering (2QF). However, since ratio field strength, ωrf/2π, spinning frequency, ωr/2π, lower, it possible operate...
Multidrug resistance is a major challenge to cancer chemotherapy. The multidrug phenotype associated with the overexpression of adenosine triphosphate (ATP)-driven transmembrane efflux pumps in cells. Here, we report lipid membrane-coated silica-carbon (LSC) hybrid nanoparticle that targets mitochondria through pyruvate, specifically produce reactive oxygen species (ROS) under near-infrared (NIR) laser irradiation. ROS can oxidize NADH into NAD+ reduce amount ATP available for pumps....
We describe three-dimensional magic-angle-spinning NMR experiments for the simultaneous measurement of multiple carbon-nitrogen distances in uniformly (13)C,(15)N-labeled solids. The approaches employ transferred echo double resonance (TEDOR) (13)C-(15)N coherence transfer and (15)N (13)C frequency labeling site-specific resolution, build on several previous 3D TEDOR techniques. novel feature pulse sequences presented here is that they are specifically designed to circumvent detrimental...
Large pore MCM-41 silica with the diameter of 5.0 nm was chemically modified by bonding monomeric-type ligands, such as trimethylsilyl, butyldimethylsilyl, and octyldimethylsilyl, well polymeric-type 3-aminopropylsilyl, (hexanoyl-3-aminopropyl)silyl, octylsilyl ligands. The obtained materials were characterized using elemental analysis, high-resolution thermogravimetry (TGA), nitrogen adsorption at 77 K in a wide range pressures. Surface coverages bonded ligands between 2.5 3.0 μmol/m2. It...
The three-dimensional structure of the chemotactic peptide N- formyl- l -Met- -Leu- -Phe-OH was determined by using solid-state NMR (SSNMR). set SSNMR data consisted 16 13 C– 15 N distances and 18 torsion angle constraints (on 10 angles), recorded from uniformly C, N-labeled samples. peptide's calculated means simulated annealing a newly developed protocol that ensures all conformational space, consistent with structural constraints, is searched completely. result high-quality molecule has...
The molecular conformation of peptide fragment 105–115 transthyretin, TTR(105–115), previously shown to form amyloid fibrils in vitro , has been determined by magic-angle spinning solid-state NMR spectroscopy. 13 C and 15 N linewidth measurements indicate that TTR(105–115) forms a highly ordered structure with each amino acid unique environment. 2D C- N- chemical shift correlation experiments, performed on three fibril samples uniformly C, N-labeled consecutive stretches 4 aa, allowed the...
We describe a magic-angle spinning NMR experiment for selective 13C−15N distance measurements in uniformly 13C,15N-labeled solids, where multiple and 13C−13C interactions complicate the accurate measurement of structurally interesting, weak dipolar couplings. The new experiment, termed FSR (frequency REDOR), combines REDOR pulse sequence with frequency spin−echo to recouple single interaction spin system. Concurrently remaining couplings all scalar selected 13C are suppressed. coupling...
Mmm—stacks of donuts! A one-dimensional n-type nanotube was formed by stacking rings from the bolaamphiphilic self-assembly 1,4,5,8-naphthalenetetracarboxylic acid diimide (NDI) with L-lysine headgroups (see picture). Solid-state NMR studies demonstrate exceptional conformational homogeneity constituent molecules that make up nanotubes. Detailed facts importance to specialist readers are published as "Supporting Information". Such documents peer-reviewed, but not copy-edited or typeset. They...
A C-terminally truncated Y145Stop variant of the human prion protein (huPrP23–144) is associated with a hereditary amyloid disease known as PrP cerebral angiopathy. Previous studies have shown that recombinant huPrP23–144 can be efficiently converted in vitro to fibrillar state, and residues 138 139 play critical role amyloidogenic properties this protein. Here, we used magic-angle spinning solid-state NMR spectroscopy provide high-resolution insight into backbone conformation dynamics...
Amyloid aggregates of a C-truncated Y145Stop mutant human prion protein, huPrP23-144, associated with heritable amyloid angiopathy, have previously been shown to contain compact, relatively rigid, and beta-sheet-rich approximately 30-residue core near the C-terminus under physiologically relevant conditions. In contrast, remaining huPrP23-144 residues display considerable conformational dynamics, as evidenced by absence corresponding signals in cross-polarization (CP)-based solid-state NMR...
Magic-angle-spinning solid-state nuclear magnetic resonance (SSNMR) studies of natively diamagnetic uniformly 13C,15N-enriched proteins, intentionally modified with side chains containing paramagnetic ions, are presented, the aim using concomitant relaxation enhancements (PREs) as a source long-range structural information. The ions incorporated at selected sites in protein EDTA−metal complexes by introducing solvent-exposed cysteine residue site-directed mutagenesis, followed modification...
The N-terminal fusion domain of the HIV-1 gp41 envelope glycoprotein is responsible for initiating viral and cellular membranes, leading to subsequent infection host cell by HIV-1. We have investigated backbone structure dynamics 30 residues in membrane-mimicking environments using NMR spectroscopy 15N- 15N,13C,2H-labeled peptides. Similar 15N−1H HSQC spectra were obtained a variety detergents, including SDS, DPC, mixed DPC/SDS, LPPG micelles, indicating that peptide not strongly influenced...
Magic-angle spinning NMR studies of 13C,15N-enriched proteins containing a covalently attached nitroxide spin label are presented, with the goal using paramagnetic relaxation enhancements in solid state to obtain long-range structural restraints. A 56 aa protein, B1 immunoglobulin-binding domain protein G (GB1), was used as model system, labels incorporated at residues 28 (α-helix) or 53 (β4-strand) via site-directed labeling. The presence GB1 analogues results negligible pseudocontact...
Chromatin is a supramolecular assembly of DNA and histone proteins, organized into nucleosome repeat units. The dynamics chromatin organization regulates accessibility to eukaryotic transcription repair complexes. Yet, the structural dynamic properties at high concentrations characteristic cellular environment (>∼200 mg/mL) are largely unexplored molecular level. Here, we apply MAS NMR directly probe protein regions in (13)C,(15)N-enriched recombinant arrays conditions designed emulate...
Protein magic angle spinning (MAS) NMR spectroscopy has generated structural models of several amyloid fibril systems, thus providing valuable information regarding the forces and interactions that confer extraordinary stability architecture. Despite these advances, however, obtaining atomic resolution describing higher levels organization within fibrils remains a significant challenge. Here, we detail MAS experiments sample labeling schemes designed specifically to probe such order...
Assembly call: The 1D self-assembly of tube-forming NDI–lysine amphiphiles in water is described. Nanotubes formed from an acid or ester give nanotubes with small inner diameters 4–5 nm, whereas the corresponding amide coils into ranging 100–200 nm (see TEM images). Spectroscopic measurements indicate presence highly ordered, homogeneous structures significant π–π interactions. Detailed facts importance to specialist readers are published as ”Supporting Information”. Such documents...
ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXT2D Covalent Organic Frameworks with Alternating Triangular and Hexagonal PoresLuke A. Baldwin, Jonathan W. Crowe, Matthew D. Shannon, Christopher P. Jaroniec, Psaras L. McGrier*View Author Information Department of Chemistry & Biochemistry, The Ohio State University, Columbus, 43210, United States*P. McGrier. E-mail: [email protected]Cite this: Chem. Mater. 2015, 27, 18, 6169–6172Publication Date (Web):August 2015Publication History Received1...
Abstract One of the most puzzling aspects prion diseases is intricate relationship between strains and interspecies transmissibility barriers. Previously we have shown that certain fundamental mammalian propagation, including strain phenomenon species barriers, can be reproduced in vitro seeded fibrillization Y145Stop protein variant. Here, use solid-state nuclear magnetic resonance spectroscopy to gain atomic level insight into structural differences amyloids from three species: human,...
We demonstrate constraint of peptide backbone and side-chain conformation with 3D 1H−15N−13C−1H dipolar chemical shift, magic-angle spinning NMR experiments. In these experiments, polarization is transferred from 15N[i] by ramped SPECIFIC cross to the 13Cα[i], 13Cβ[i], 13Cα[i − 1] resonances evolves coherently under correlated 1H−15N 1H−13C couplings. The resulting set frequency-labeled 15N1H−13C1H spectra depend strongly upon molecular torsion angles φ[i], χ1[i], ψ[i 1]. To interpret data...