A5021963607- Enzyme Structure and Function
- Advanced X-ray Imaging Techniques
- Protein Structure and Dynamics
- Genetic Neurodegenerative Diseases
- Lipid Membrane Structure and Behavior
- Chalcogenide Semiconductor Thin Films
- Spectroscopy and Quantum Chemical Studies
- Advanced Chemical Physics Studies
- Mitochondrial Function and Pathology
- RNA and protein synthesis mechanisms
- Electrochemical Analysis and Applications
- Nanoparticle-Based Drug Delivery
- X-ray Spectroscopy and Fluorescence Analysis
- Advanced Semiconductor Detectors and Materials
- Semiconductor Quantum Structures and Devices
- Amyotrophic Lateral Sclerosis Research
- Hydrogels: synthesis, properties, applications
- Viral Infections and Outbreaks Research
- Perovskite Materials and Applications
- Surfactants and Colloidal Systems
- Viral Infections and Vectors
- Ubiquitin and proteasome pathways
- Protein Interaction Studies and Fluorescence Analysis
- Atmospheric chemistry and aerosols
- Laser Material Processing Techniques
National Synchrotron Radiation Research Center
2015-2025
Vitenparken
2018
University of California, Berkeley
2011-2017
University of California System
2014
Berkeley College
2014
Lawrence Berkeley National Laboratory
2013
Sony Computer Science Laboratories
1994-1998
Sony Corporation (United States)
1995
Massachusetts Institute of Technology
1990-1992
Recent developments in the instrumentation and data analysis of synchrotron small-angle X-ray scattering (SAXS) on biomolecules solution have made biological SAXS (BioSAXS) a mature popular tool structural biology. This article reports an advanced endstation developed at beamline 13A 3.0 GeV Taiwan Photon Source for small- wide-angle (SAXS-WAXS or SWAXS). The features in-vacuum SWAXS detection system comprising two mobile area detectors (Eiger X 9M/1M) online size-exclusion chromatography...
The formation of like-charge guanidinium-guanidinium contact ion pairs in water is evidenced and characterized by X-ray absorption spectroscopy first-principles spectral simulations based on molecular dynamics sampling. Observed concentration-induced nitrogen K-edge resonance shifts result from π* state mixing the release molecules each first solvation sphere as two solvated guanidinium ions associate into a stacked pair configuration. Possible biological implications this counterintuitive...
We report a combined theoretical and experimental study of the water octamer-h16. The calculations used ring-polymer instanton method to compute tunnelling paths splittings in full dimensionality. experiments measured extensive high resolution spectra near 1.4 THz, for which isotope dilution group analysis support assignment octamer. Transitions appear as singlets, consistent with paths, involve breakage two hydrogen-bonds thus give tunneling below resolution.
Hydration plays a crucial role in regulating the dispersion behavior of biomolecules water, particularly how pH-sensitive hydration water network forms around proteins. This study explores conformation and structure Type-I tropocollagen using small- wide-angle X-ray scattering (SWAXS) molecular dynamics (MD) simulations. The results reveal that exhibits significant softening solution, transitioning from its rod-like tissues to worm-like conformation, characterized by reduced radius gyration...
Since their introduction into the commercial marketplace in 1991, lithium ion batteries have become increasingly ubiquitous portable technology. Nevertheless, improvements to existing battery technology are necessary expand utility for larger-scale applications, such as electric vehicles. Advances may be realized from liquid electrolyte; however, current understanding of structure and properties remains incomplete. X-ray absorption spectroscopy solutions LiBF4 propylene carbonate (PC),...
Using simultaneously scanning small-angle X-ray scattering (SAXS) and UV-vis absorption with integrated online size exclusion chromatography, supplemental molecular dynamics simulations, we unveil the long-postulated global structure evolution of a model multidomain protein bovine serum albumin (BSA) during acid-induced unfolding. Our results differentiate three packing structures molten globule domains BSA, forming intermediates I1, I2, E along unfolding pathway. The I1-I2 transition,...
Abstract The synthesis of the cell-wall peptidoglycan during bacterial cell division is mediated by a multiprotein machine, called divisome. essential membrane protein complex FtsB, FtsL and FtsQ (FtsBLQ) at heart divisome assembly cascade in Escherichia coli . This regulates transglycosylation transpeptidation activities FtsW-FtsI PBP1b via coordination with FtsN, trigger for onset constriction. Yet underlying mechanism FtsBLQ-mediated regulation largely unknown. Here, we report full-length...
Nitrate and nitrite ions are of considerable interest, both for their widespread use in commercial research contexts because central role the global nitrogen cycle. The chemistry atmospheric aerosols, wherein nitrate is abundant, has been found to depend on interfacial behavior ionic species. determined largely by hydration properties; consequently, study comprises a significant field study. In this work, we describe aqueous solutions sodium via X-ray absorption spectroscopy (XAS),...
Chikungunya virus (CHIKV) is a mosquito-borne alphavirus responsible for chikungunya fever. Nonstructural protein 2 (nsP2), multifunctional essential viral replication, has an N-terminal helicase region (nsP2h), which both nucleotide triphosphatase and RNA activities, as well C-terminal cysteine protease (nsP2p), nonstructural polyprotein processing. The two functional units are connected through linker of 14 residues. Although crystal structures the regions CHIKV nsP2 have been solved...
The optical design and performance of the recently opened 13A biological small-angle X-ray scattering (SAXS) beamline at 3.0 GeV Taiwan Photon Source National Synchrotron Radiation Research Center are reported. is designed for studies structures kinetics in a wide range length time scales, from angstrom to micrometre microsecond minutes. A 4 m IU24 undulator provides high-flux X-rays energy 4.0-23.0 keV. MoB
The presence of organic surfactants in atmospheric aerosol may lead to a depression cloud droplet growth and evaporation rates affecting the radiative properties lifetime clouds. Both magnitude mechanism this effect, however, remain poorly constrained. We have used Raman thermometry measurements freely evaporating micro-droplets determine coefficients for several concentrations acetic acid, which is ubiquitous has been shown adsorb strongly air–water interface. find no suppression kinetics...
Hexanucleotide repeat expansion in C9ORF72 ( C9 ) is the most prevalent mutation among amyotrophic lateral sclerosis (ALS) patients. The patients carry over ~30 to hundreds or thousands of repeats translated dipeptide (DPRs) where poly-glycine-arginine (GR) and poly-proline-arginine (PR) are toxic. structure-function relationship still unknown. Here, we examined minimal neurotoxic number poly-GR found that extension led a loose helical structure disrupting plasma nuclear membrane. Poly-GR/PR...
The aberrant fibrillization of huntingtin exon 1 (Httex1) characterized by an expanded polyglutamine (polyQ) tract is a defining feature Huntington's disease, neurodegenerative disorder. Recent investigations underscore the involvement small EDRK-rich factor 1a (SERF1a) in promoting Httex1 through interactions with its N terminus. By establishing integrated approach size-exclusion-column-based small- and wide-angle X-ray scattering (SEC-SWAXS), NMR, molecular simulations using Rosetta ,...
Spatial hindrance-based pro-antibodies (pro-Abs) are engineered antibodies to reduce monoclonal antibodies' (mAbs) on-target toxicity using universal designed blocking segments that mask mAb antigen-binding sites through spatial hindrance. By linking protease substrates and linkers, these can be removed site-specifically. Although many types of have been developed, such as coiled-coil hinge-based Ab locks, the molecular structure pro-Ab, particularly region showing how fragment blocks mAb,...
The Green’s function temperature expressions formulated by McGahan and Cole [J. Appl. Phys. 72, 1362 (1992)] are modified into a form suitable for solving the heat conduction problem encountered in magneto-optical (MO) disk recording situations. distribution within MO multilayer media heated pulsed scanning Gaussian laser beam is calculated using Fourier-transformed functions. linear equation solved exactly not real space but frequency space. efficiently recovered inverse fast Fourier...
Liposome development is of great interest owing to increasing requirements for efficient drug carriers. The structural features and thermal stability such liposomes are crucial in transport delivery. Reported here the results characterization PEGylated via small- wide-angle X-ray scattering an asymmetric flow field-flow fractionation (AF4) system coupled with differential refractive-index detection, multi-angle light (MALS) dynamic scattering. This integrated analysis exemplar liposome...
Direct binding of calcium ions (Ca2+) to phospholipid membranes is an unclarified yet critical signaling pathway in diverse Ca2+-regulated cellular phenomena. Here, high-pressure-liquid-chromatography, small-angle X-ray scattering (SAXS), UV–vis absorption, and differential refractive index detections are integrated probe Ca2+-binding the zwitterionic lipid nanodiscs. The responses upon Ca2+-binding, composition conformation, quantified through data analysis. results indicate that Ca2+ binds...
Multivalent ligands hold promise for enhancing avidity and selectivity to simultaneously target multimeric proteins, as well potentially modulating receptor signaling in pharmaceutical applications. Essential these manipulations are nanosized scaffolds that precisely control ligand display patterns, which can be achieved by using polyproline oligo-helix macrocyclic nanoscaffolds
Poly(ethylene oxide) in butanol reveals two exotherms differential scanning calorimetry (DSC) scans during cooling and endotherms DSC heating. Using small-angle X-ray scattering (SAXS) wide-angle diffraction (WAXD) to characterize structural evolutions cooling, annealing, heating, we found that the thermal behavior is related poly(ethylene (PEO) crystallization, PEO gelation, complexation. The low exotherm (Texo,L) endotherm (Tendo,L) correspond heat flows resulting from crystallization...
This study unveils the "green" metal-organic framework (MOF) structuring mechanism by decoding proton transfer in water during ZIF-8 synthesis. Combining
Amphiphilic block copolymer (a-BCP) micelles offer morphological diversity and dimensional tunability, making them suitable for the fabrication of perovskite nanocrystals. However, precise control over nucleation growth nanocrystals using a-BCP colloidal templates remains underexplored. This study investigates effects toluene, methanol, polystyrene-block-poly(2-vinylpyridine) (PS-b-P2VP) on formation cesium lead bromide (CsPbBr3) The process involves four stages: (i) PS-b-P2VP micellization,...
Borohydride salts have been considered as good prospects for transportable hydrogen storage materials, with molecular released via hydrolysis. We examine details of the hydration sodium borohydride by combination X-ray absorption spectroscopy and first principles' theory. Compared to solid borohydride, aqueous sample exhibits an uncharacteristically narrow feature that is shifted lower energy, ascribed formation dihydrogen bonds between water weaken boron-hydrogen covalent bonds. Water also...