A5021960485- Electron Spin Resonance Studies
- Lanthanide and Transition Metal Complexes
- Magnetism in coordination complexes
- Advanced NMR Techniques and Applications
- Supramolecular Chemistry and Complexes
- Molecular Sensors and Ion Detection
- Protein Structure and Dynamics
- Enzyme Structure and Function
- Photosynthetic Processes and Mechanisms
- Advanced MRI Techniques and Applications
- Surfactants and Colloidal Systems
- Molecular Junctions and Nanostructures
- Protein Interaction Studies and Fluorescence Analysis
- Mass Spectrometry Techniques and Applications
- Metal complexes synthesis and properties
- Biotechnology and Related Fields
- Supramolecular Self-Assembly in Materials
- Heat shock proteins research
- Electrocatalysts for Energy Conversion
- NMR spectroscopy and applications
- Analytical Chemistry and Chromatography
- Metal-Catalyzed Oxygenation Mechanisms
- Retinoids in leukemia and cellular processes
- National Identity and Symbolism
- Crystallography and molecular interactions
Bioénergétique et Ingénierie des Protéines
2012-2024
Aix-Marseille Université
2013-2024
Centre National de la Recherche Scientifique
2014-2024
Institut de Microbiologie de la Méditerranée
2012-2023
University of Bologna
2006-2011
University of Miami
2009
Approaching protein structural dynamics and protein-protein interactions in the cellular environment is a fundamental challenge. Owing to its absolute sensitivity selectivity paramagnetic species, site-directed spin labeling (SDSL) combined with electron resonance (EPR) has potential evolve into an efficient method follow conformational changes proteins directly inside cells. Until now, use of nitroxide-based labels for in-cell studies represented major hurdle because their short persistence...
The combined effects of the cellular environment on proteins led to definition a fifth level protein structural organization termed quinary structure. To explore implication potential structure for globular proteins, we studied dynamics and conformations Escherichia coli (E. coli) peptidyl-prolyl cis/trans isomerase B (PpiB) in E. cells. PpiB plays major role maturation regulation folded by catalyzing isomerization proline imidic peptide bond. We applied electron paramagnetic resonance (EPR)...
Beyond stripes: The extreme lipophobicity of perfluorinated chains attached to amphiphilic thiolates triggers the formation "stars" (or patches) surrounded by alkylthiolates in three-dimensional self-assembled monolayers. This strategy led first example a water-soluble multicompartment monolayer wrapped around gold core.
Keeping tabs on tyrosine: A three-component Mannich-type reaction extends the scope of site-directed spin labeling by selectively unique tyrosine residue CP12 protein (see picture), as was confirmed mass spectrometry. EPR spectroscopy labeled showed a very high mobility probe, which remained mobile after complex formation with GAPDH.
Site-directed spin labeling (SDSL) combined with electron paramagnetic resonance (EPR) spectroscopy has emerged as a powerful approach to study structure and dynamics in proteins. One limitation of this is the fact that classical labels are functionalized be grafted on natural or site-directed mutagenesis generated cysteine residues. Despite widespread success cysteine-based modification strategies, technique becomes unsuitable when residues play functional structural role protein under...
Site‐directed spin labeling (SDSL) combined with continuous wave electron paramagnetic resonance (cw EPR) spectroscopy is a powerful technique to reveal, at the residue level, structural transitions in proteins. SDSL‐EPR based on selective grafting of label protein under study, followed by cw EPR analysis. To extract valuable quantitative information from spectra and thus give reliable interpretation biological system dynamics, numerical simulations are required. Such spectral can be carried...
A growing body of literature on intrinsically disordered proteins (IDPs) led scientists to rethink the structure-function paradigm protein folding. Enzymes are often considered an exception rule intrinsic disorder (ID), believed require a unique structure for catalysis. However, recent studies revealed presence in several functional native enzymes. In present work, we address importance dynamics catalysis, by investigating relationship between folding and activity Sporosarcina pasteurii UreG...
The conformational landscape of UreG was investigated in bacteria by in-cell EPR In-cell gives access to structural information a physiological environmentThe co-existence an extended and compact conformation found cellThe flexibility could regulate its enzymatic activity
The role of intramolecular hydrogen bonding (HB) on the bond-dissociation enthalpy (BDE) phenolic O-H and kinetics H-atom transfer to peroxyl radicals (k(inh)) several 2-alkoxyphenols was experimentally quantified by EPR equilibration technique inhibited autoxidation studies. These compounds can be regarded as useful models for studying abstraction from 2-OR phenols, such many lignans, reduced coenzyme Q curcumin. effects various substituents BDE(O-H) 2-methoxy, 2-methoxy-4-methyl,...
Site-directed spin labeling of native tyrosine residues in isolated domains the protein PTBP1, using a Mannich-type reaction, was combined with conventional cysteine residues. Double electron–electron resonance (DEER) EPR measurements were performed for both nitroxide–nitroxide and Gd(III)–nitroxide label combinations within same molecule. For prediction distance distributions from structure model, rotamer libraries generated two linker forms tyrosine-reactive isoindoline-based nitroxide...
Abstract Approaching protein structural dynamics and protein–protein interactions in the cellular environment is a fundamental challenge. Owing to its absolute sensitivity selectivity paramagnetic species, site‐directed spin labeling (SDSL) combined with electron resonance (EPR) has potential evolve into an efficient method follow conformational changes proteins directly inside cells. Until now, use of nitroxide‐based labels for in‐cell studies represented major hurdle because their short...
Cool threads! Complete solubilisation of cucurbit[8]uril was observed when the macrocycle dissolved in a water solution containing protonated 4-amino-2,2,6,6-tetramethyl piperidine-N-oxyl. Slow cooling this to 5 °C led formation long fibrous network (see figure).
CP12 is a widespread regulatory protein of oxygenic photosynthetic organisms that contributes to the regulation Calvin cycle by forming supra-molecular complex with at least two enzymes: glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and phosphoribulokinase (PRK). shares some similarities intrinsically disordered proteins (IDPs) depending on its redox state. In this study, site-directed spin labeling (SDSL) combined EPR spectroscopy was used probe dynamic behavior from Chlamydomonas...
Abstract One of the greatest current challenges in structural biology is to study protein dynamics over a wide range timescales complex environments, such as cell. Among magnetic resonances suitable for this approach, electron paramagnetic resonance spectroscopy coupled site‐directed spin labeling (SDSL‐EPR) has emerged promising tool local and conformational ensembles. In work, we exploit sensitivity nitroxide labels report at room temperature. We demonstrate that studies can be performed...
In quarantine: Nitroxide spin probes are encapsulated by hexameric resorcinarene molecular capsules in dichloromethane solutions (see picture). A substantial reduction the tumbling rates occurs upon encapsulation of two cationic and one neutral probe. As volume probe increases, rate reflects overall entire supramolecular assembly.
Molecular recognition is central to all biological processes. Understanding the key role played by dedicated chaperones in metalloprotein folding and assembly requires knowledge of their conformational ensembles. In this study, NarJ chaperone membrane-bound respiratory nitrate reductase complex NarGHI, a molybdenum-iron containing metalloprotein, was taken as model chaperone. The combination two techniques ie site-directed spin labeling followed EPR spectroscopy ion mobility mass...
The first example of paramagnetic rotaxane containing cucurbit[6]urils has been reported and characterized both by ESR NMR spectroscopy.
Site-directed spin labeling (SDSL) combined with continuous wave electron paramagnetic resonance (cw EPR) spectroscopy is a powerful technique to reveal, at the local level, dynamics of structural transitions in proteins. Here, we consider SDSL-EPR based on selective grafting nitroxide protein under study, followed by X-band cw EPR analysis. To extract valuable quantitative information from spectra and thus give reliable interpretation biological system dynamics, numerical simulation...
Experimental evidence for the generation of radicals by Me2Zn used in Reformatsky reactions was unequivocally established with a radical trap.
Site Directed Spin Labeling (SDSL) combined with EPR spectroscopy is a very powerful approach to investigate structural transitions in proteins particular flexible or even disordered ones. Conventional spin labels are based on nitroxide derivatives leading classical 3-line spectra whose spectral shapes indicative of the environment and thus constitute good reporters modifications. However, similarity these precludes probing two regions protein partner simultaneously. To overcome limitation...