A5028382987- Enzyme Structure and Function
- Protein Structure and Dynamics
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Organometallic Complex Synthesis and Catalysis
- Lipid Membrane Structure and Behavior
- Surfactants and Colloidal Systems
- Supramolecular Self-Assembly in Materials
- Proteins in Food Systems
- Bacteriophages and microbial interactions
- Advanced X-ray Imaging Techniques
- RNA and protein synthesis mechanisms
- Organometallic Compounds Synthesis and Characterization
- Synthesis and characterization of novel inorganic/organometallic compounds
- Crystallography and molecular interactions
- Metal complexes synthesis and properties
- Protein purification and stability
- RNA Research and Splicing
- Material Dynamics and Properties
- X-ray Spectroscopy and Fluorescence Analysis
- Chemical Synthesis and Analysis
- Enzyme Production and Characterization
- RNA modifications and cancer
- Analytical Chemistry and Chromatography
- Spectroscopy and Quantum Chemical Studies
Synchrotron soleil
2016-2025
Bellvitge University Hospital
2024
University of Colorado Boulder
2023
Mothers’ Milk Bank
2023
Children's Hospital of Philadelphia
2023
Elkhorn Slough Foundation
2023
Beam Engineering for Advanced Measurements (United States)
2021-2022
Universidade de Vigo
2021
Institut Català d'Oncologia
2003-2018
Universidad Nacional Autónoma de México
1996-2018
Small-angle X-ray scattering for macromolecules in solution is now widely used structural biology to complement high-resolution structure determination obtained by crystallography or NMR. In the context of third-generation synchrotron sources, this increasing interest leads developments sample environments and automation. The presence an online purification system justified need monodispersity. A combined including auto-sampler robot high-performance liquid chromatography (HPLC) has been...
In 2012, preliminary guidelines were published addressing sample quality, data acquisition and reduction, presentation of scattering validation, modelling for biomolecular small-angle (SAS) experiments. Biomolecular SAS has since continued to grow authors have increasingly adopted the guidelines. parallel, integrative/hybrid determination structures is a rapidly growing field that expanding scope structural biology. For contribute maximally this field, it essential ensure open access...
The X-ray structure of (Tl[Au(C(6)Cl(5))(2)])(n), 1, consists 1-D linear polymer chains parallel to the crystallographic z axis. crystal 1 has channels that run these with interatom distances in range 3.231-4.076 A. There are holes diameters as large 10.471 A, which can accommodate a variety solvents. Complex displays reversible vapochromic emission and absorption spectral behavior when solid is exposed organic vapors such acetone, acetonitrile, triethylamine, acetylacetone,...
By combining the osmotic stress technique with small-angle x-ray scattering measurements, we followed structural response of casein micelle to an overall increase in concentration. When aqueous phase that separates micelles is extracted, they behave as polydisperse repelling spheres and their internal structure not affected. are compressed, lose water shrink a smaller volume. Our results indicate this compression nonaffine, i.e., some parts collapse, whereas other resist deformation. We...
In the mouth, proline-rich proteins (PRP), which are major components of stimulated saliva, interact with tannins contained in food. We report vitro interactions tannin epigallocatechin gallate (EgCG), a basic salivary PRP, IB5, studied through electrospray ionization mass spectrometry (ESI-MS), small-angle X-ray scattering (SAXS), and dynamic light (DLS). dilute protein (IB5) solutions low ionic strength (1 mM), repel each other, bind to nonaggregated proteins. ESI-MS experiments determine...
Size-exclusion chromatography coupled with SAXS (small-angle X-ray scattering), often performed using a flow-through capillary, should allow direct collection of monodisperse sample data. However, capillary fouling issues and non-baseline-resolved peaks can hamper its efficacy. The UltraScan solution modeler (US-SOMO) HPLC-SAXS (high-performance liquid SAXS) module provides comprehensive framework to analyze such data, starting simple linear baseline correction symmetrical Gaussian...
Small-angle X-ray scattering (SAXS) of proteins in solution has become a key tool for biochemists and structural biologists, thanks especially to the availability beamlines with high-throughput capabilities at synchrotron sources. Despite large spectrum scientific disciplines tackled on SWING beamline since its opening 2008, there always been strong commitment offering state-of-the-art biological SAXS (BioSAXS) instrumentation data reduction methods community. The extremely reliable...
Grape and apple condensed tannin fractions were autoxidized at high concentrations (5 g/L) in aqueous solutions analyzed by thiolysis (depolymerization followed HPLC analysis) small angle X-ray scattering (SAXS). Structural parameters of native (unoxidized) polymers derived from SAXS according to the wormlike chain model: length per monomer is 15 Å, statistical segment 17 cross section macromolecule has a radius within range 3−4.5 Å. The rather short an effect different location...
The structural and photophysical properties of a new series cationic neutral Au(I) dinuclear compounds (1 2, respectively) bridged by bis(diphenylphosphino)methane (dppm) substituted benzimidazolethiolate (X-BIT) ligands, where X = H (a), Me (b), OMe (c), Cl (d), have been studied. Monocationic complexes, [A(u2)(micro-X-BIT)(micro-dppm)](CF(3)CO(2)), were prepared the reaction [A(u2)(micro-dppm)](CF(3)CO(2))(2) with 1 equiv X-BIT in excellent yields. cations 1a-1d possess similar molecular...
Solubilization of integral membrane proteins in aqueous solutions requires the presence amphiphilic molecules like detergents. The transmembrane region is then surrounded by a corona formed these molecules, ensuring hydrophilic outer surface. this has strongly hampered structural studies solubilized small-angle X-ray scattering (SAXS), technique frequently used to monitor conformational changes soluble proteins. Through online combination size exclusion chromatography, SAXS, and...
Microbial glycolipids are a class of well-known compounds, but their self-assembly behavior is still not well understood. While the free carboxylic acid end group makes some them interesting stimuli-responsive sugar hydrophilic and nature fatty chain make understanding in water easy highly unpredictable. Using cryo-transmission electron microscopy (cryo-TEM) both pH-dependent situ ex small angle X-ray scattering (SAXS), we demonstrate that aqueous at room temperature (RT) family β-d-glucose...
Abstract Controlled protein assembly provides a means to regulate function. Supramolecular building blocks, including rigid macrocycles, are versatile triggers of assembly. Now it is shown that sulfonato‐calix[8]arene ( sclx 8 ) mediates the formation cytochrome c tetramers in solution. This tetramer spontaneously disassembles at ≥2 equivalents , providing remarkable example auto‐regulation. Using X‐ray crystallography binding sites on were characterized. Crystal structures different...
The linear-chain polymer {Tl[Au(C6Cl5)2]}n, 1, reacts in the solid state and solution with different volatile organic compounds such as tetrahydrofuran, acetone, tetrahydrothiophene, 2-fluoropyridine, acetonitrile, acetylacetone, pyridine. Solid-state exposure of 1 to vapors above VOCs produces a selective reversible change its color that is perceptible human eye even deeper under UV irradiation, allowing function sensor for these VOCs. Heating samples exposed few minutes at 100° C...
The nanostructure of a peptide amphiphile in commercial use anti-wrinkle creams is investigated. contains matrikine, collagen-stimulating, pentapeptide sequence. Self-assembly into giant nanotapes observed and the internal structure was found to comprise bilayers parallel flat tape surfaces.
Fibrinogen is a large heterogeneous aggregation/degradation-prone protein playing central role in blood coagulation and associated pathologies, whose structure not completely resolved. When high-molecular-weight fraction was analyzed by size-exclusion high-performance liquid chromatography/small-angle X-ray scattering (HPLC-SAXS), several composite peaks were apparent because of the stickiness fibrinogen analysis complicated severe capillary fouling. Novel SAS tools developed as part...
The micellar structure of sophorolipids, a glycolipid bolaamphiphile, is analyzed using combination small-angle X-ray scattering (SAXS), neutron (SANS), and molecular dynamics (MD) simulations. Numerical modeling SAXS curves shows that morphology in the noncharged system (pH< 5) made prolate ellipsoids revolution with core-shell morphology. Opposed to most surfactant systems, hydrophilic shell has nonhomogeneous distribution matter: thickness axial direction ellipsoid found be practically...
Structural studies of integral membrane proteins have been limited by the intrinsic conformational flexibility and need to stabilize in solution. Stabilization mutagenesis was very successful for structural biology G protein-coupled receptors (GPCRs). However, it requires heavy protein engineering may introduce deviations. Here we describe use specific calixarenes-based detergents native GPCR stabilization. Wild type, full length human adenosine A2A receptor used exemplify approach. We could...