A5013024407- Advanced NMR Techniques and Applications
- Lipid Membrane Structure and Behavior
- Solid-state spectroscopy and crystallography
- Protein Structure and Dynamics
- NMR spectroscopy and applications
- Antimicrobial Peptides and Activities
- Electron Spin Resonance Studies
- Polysaccharides and Plant Cell Walls
- Ionic liquids properties and applications
- Influenza Virus Research Studies
- RNA and protein synthesis mechanisms
- Supramolecular Self-Assembly in Materials
- Advanced MRI Techniques and Applications
- Bacteriophages and microbial interactions
- Alzheimer's disease research and treatments
- Muon and positron interactions and applications
- Advanced Cellulose Research Studies
- DNA and Nucleic Acid Chemistry
- Plant nutrient uptake and metabolism
- RNA Interference and Gene Delivery
- Advanced Neuroimaging Techniques and Applications
- Infectious Encephalopathies and Encephalitis
- Crystallization and Solubility Studies
- Distributed and Parallel Computing Systems
- Molecular spectroscopy and chirality
Massachusetts Institute of Technology
2016-2025
Huazhong University of Science and Technology
2025
Union Hospital
2025
Liaoning University
2006-2023
Hefei University
2023
Peking University
2007-2018
Hubei University of Technology
2016
Changchun University
2016
Inner Mongolia Normal University
2015
Iowa State University
2005-2014
The polysaccharide-rich cell walls (CWs) of plants perform essential functions such as maintaining tensile strength and allowing plant growth. Using two- three-dimensional magic-angle-spinning (MAS) solid-state NMR uniformly 13C-labeled Arabidopsis thaliana, we have assigned the resonances major polysaccharides in intact insoluble primary CW determined intermolecular contacts dynamics cellulose, hemicelluloses, pectins. Cellulose microfibrils showed extensive interactions with pectins, while...
The M2 protein of influenza viruses forms an acid-activated tetrameric proton channel. We used solid-state nuclear magnetic resonance spectroscopy to determine the structure and functional dynamics pH-sensing proton-selective histidine-37 in bound a cholesterol-containing virus-envelope-mimetic membrane so as better understand conduction mechanism. In high-pH closed state, four histidines form edge-face π-stacked structure, preventing formation hydrogen-bonded water chain conduct protons....
The design of functional membrane proteins from first principles represents a grand challenge in chemistry and structural biology. Here, we report the membrane-spanning, four-helical bundle that transports first-row transition metal ions Zn 2+ Co , but not Ca across membranes. conduction path was designed to contain two di-metal binding sites bind with negative cooperativity. X-ray crystallography solid-state solution nuclear magnetic resonance indicate overall helical is formed tightly...
Histidine structure and chemistry lie at the heart of many enzyme active sites, ion channels, metalloproteins. While solid-state NMR spectroscopy has been used to study histidine chemical shifts, full pH dependence complete panel 15N, 13C, 1H shifts sensitivity these tautomeric have not reported. Here we use magic-angle-spinning determine from 4.5 11. Two-dimensional homonuclear heteronuclear correlation spectra indicate that depend sensitively on protonation state structure. The rare π...
Significance The protein expansin loosens the cell walls of plants for growth, but its carbohydrate target binding has been elusive because difficulty studying noncrystalline plant wall by most structural biology techniques and trace amount needed loosening. We have now combined dynamic nuclear polarization sensitivity-enhanced solid-state NMR spectroscopy with 13 C labeling Arabidopsis thaliana C, 15 N expansin, to determine that binds cellulose microfibrils loosen wall. site is enriched in...
The structural role of pectins in plant primary cell walls is not yet well understood because the complex and disordered nature wall polymers. We recently introduced multidimensional solid-state nuclear magnetic resonance spectroscopy to characterize spatial proximities polysaccharides. data showed extensive cross peaks between cellulose Arabidopsis (Arabidopsis thaliana), indicating subnanometer contacts two This result was unexpected stable pectin-cellulose interactions are predicted by...
It is known that smooth, hydrophobic solid surfaces exhibit low ice adhesion values, which have been shown to approach a lower strength limit (∼150 kPa) defined by the water receding contact angle. To overcome this limit, we designed self-lubricating icephobic coatings blending polydimethylsiloxane (PDMS)-poly(ethylene glycol) (PEG) amphiphilic copolymers into polymer matrix. Such provide values (∼50 can substantially reduce bound of achieved previously on surfaces. Different molecular...
We used solid-state NMR spectroscopy to investigate the oligomeric structure and insertion of protegrin-1 (PG-1), a beta-hairpin antimicrobial peptide, in lipid bilayers that mimic either bacterial inner membrane [palmitoyloleoylphosphatidyl ethanolamine palmitoyloleoylphosphatidylglycerol (POPE/POPG) bilayers] or red blood cell [neutral palmitoyloleoylphosphatidylcholine (POPC)/cholesterol bilayers]. (1)H spin diffusion from lipids peptide indicates PG-1 contacts both acyl chains headgroups...
We describe a method for determining the torsion angle φ in peptides. The technique is based on measurement of relative orientation N−HN and Cα−Hα bonds, which manifested rotational sideband spectrum sum difference two corresponding dipolar couplings. exploits 15N−13C double-quantum zero-quantum coherences, evolve simultaneously under N−H C−H interactions. magnitudes these couplings scaled by proton homonuclear decoupling sequence are directly extracted from control experiments that...
The insertion of charged amino acid residues into the hydrophobic part lipid bilayers is energetically unfavorable yet found in many cationic membrane peptides and protein domains. To understand mechanism this translocation, we measured 13C−31P distances for an Arg-rich β-hairpin antimicrobial peptide, PG-1, using solid-state NMR. Four residues, including two Arg's, scattered through peptide were chosen distance measurements. Surprisingly, all show short to 31P: 4.0−6.5 Å anionic POPE/POPG...
The mechanisms underlying the biosynthesis of cellulose in plants are complex and still poorly understood. A central question concerns mechanism microfibril structure how this is linked to catalytic polymerization action synthase (CESA). Furthermore, it remains unclear whether modification can be achieved genetically, which could transformative a bio-based economy. To explore these processes planta , we developed chemical genetic toolbox pharmacological inhibitors corresponding...
The acid-activated proton channel formed by the influenza M2 protein is important for life cycle of virus. A single histidine, His37, in transmembrane domain (M2TM) responsible pH activation and selectivity channel. Recent studies suggested three models how His37 mediates transport: a shuttle mechanism involving protonation deprotonation, H-bonded imidazole-imidazolium dimer model, transporter model large conformational changes synchrony with conduction. Using magic-angle-spinning (MAS)...
Cell-penetrating peptides (CPPs) are small cationic that cross the cell membrane while carrying macromolecular cargoes. We use solid-state NMR to investigate structure and lipid interaction of two residues, Arg(10) Lys(13), in CPP penetratin. (13)C chemical shifts indicate adopts a rigid beta-strand conformation liquid-crystalline state anionic membranes. This behavior contrasts with all other residues observed so far this peptide, which adopt dynamic beta-turn coil-like at physiological...
The primary cell wall of higher plants consists a mixture polysaccharides whose spatial proximities and interactions with each other are not well understood. We recently obtained the first two-dimensional (2D) three-dimensional high-resolution magic-angle-spinning 13C solid-state nuclear magnetic resonance spectra uniformly 13C-labeled Arabidopsis thaliana, which allowed us to assign majority resonances three major classes polysaccharides: cellulose, hemicellulose, pectins. In this work, we...
The M2 protein of influenza A viruses forms a tetrameric pH-activated proton-selective channel that is targeted by the amantadine class antiviral drugs. Its ion function has been extensively studied electrophysiology and mutagenesis; however, molecular mechanism proton transport still elusive, inhibition controversial. We review functional data on activity, dynamics simulations conduction mechanism, high-resolution structural dynamical information this membrane in lipid bilayers...
Influenza A virus M2 (A/M2) forms a homotetrameric proton selective channel in the viral membrane. It has been drug target of antiviral drugs such as amantadine and rimantadine. However, most current virulent influenza viruses carry drug-resistant mutations alongside binding site, S31N, V27A, L26F, etc., each which might be dominant given flu season. Among these mutations, V27A mutation was prevalent among transmissible under selection pressure. Until now, not successfully targeted by small...