A5044615615- Chemical Synthesis and Analysis
- Metal complexes synthesis and properties
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Molecular Sensors and Ion Detection
- DNA and Nucleic Acid Chemistry
- RNA and protein synthesis mechanisms
- Metal-Catalyzed Oxygenation Mechanisms
- Protein Structure and Dynamics
- Mass Spectrometry Techniques and Applications
- Monoclonal and Polyclonal Antibodies Research
- Biochemical and Structural Characterization
- Photoacoustic and Ultrasonic Imaging
- Supramolecular Self-Assembly in Materials
- Advanced biosensing and bioanalysis techniques
- Peptidase Inhibition and Analysis
- Ultrasound and Hyperthermia Applications
- Enzyme Structure and Function
- Antimicrobial Peptides and Activities
- Ferrocene Chemistry and Applications
- Metalloenzymes and iron-sulfur proteins
- Click Chemistry and Applications
- Trace Elements in Health
- Crystallography and molecular interactions
- Heme Oxygenase-1 and Carbon Monoxide
Centrale Marseille
2015-2024
Aix-Marseille Université
2015-2024
Centre National de la Recherche Scientifique
2015-2024
Institut des Sciences Moléculaires de Marseille
2015-2023
University of Birmingham
2021
Universidade Nova de Lisboa
2010-2017
Institut de Neurobiologie de la Méditerranée
2015
Instituto de Biologia Experimental e Tecnológica
2009-2015
Délégation Provence et Corse
2015
Instituto de Tecnología Química
2015
A dinuclear metal ion complex Zn2(L2O) and its mononuclear analogue Zn(L1OH) were synthesized studied as catalysts of the cleavage phosphate diester 2-hydroxypropyl-4-nitrophenyl (HPNP). X-ray crystal structure data, potentiometric titrations, 1H NMR spectra obtained over a wide range pH values provide strong evidence that alcohol linker in is ionized below 6.0, while group remains protonated even at high pH. The ionizations observed correspond to formation monohydroxo complexes,...
A human-bacterium symbiosis leads to the production of an antipathogenic and safe RiPP with a novel thioether network.
A series of ligands containing linked 1,4,7-triazacyclononane macrocycles are studied for the preparation dinuclear Zn(II) complexes including 1,3-bis(1,4,7-triazacyclonon-1-yl)-2-hydroxypropane (L2OH), 1,5-bis(1,4,7-triazacyclonon-1-yl)pentane (L3), 2,9-bis(1-methyl-1,4,7-triazacyclonon-1-yl)-1,10-phenanthroline (L4), and α,α'-bis(1,4,7-triazacyclonon-1-yl)-m-xylene (L5). The titration these with Zn(NO3)2 was monitored by 1H NMR. Each ligand found to bind two ions a very high affinity at...
Copper(II) complexes have been intensely investigated in a variety of diseases and pathological conditions due to their therapeutic potential. The development these requires good knowledge metal coordination chemistry ligand design control species distribution solution tailor the copper(II) centers right environment for desired biological activity. Herein we present synthesis characterization two ligands HL1 H2L2 containing phenanthroline unit (phen) attached amino group histidine (His)....
Three novel dinuclear Cu(II) complexes based on a N,N,O-chelating salphen-like ligand scaffold and bearing varying aromatic substituents (−H, −Cl, −Br) have been synthesized characterized. The experimental computational data obtained suggest that all three exist in the dimeric form solid state adopt same conformation. mass spectrometry electron paramagnetic resonance results indicate structure coexists with monomeric solution upon solvent (dimethyl sulfoxide water) coordination. exhibit high...
Extracellular hemoglobin, a byproduct of hemolysis, can release its prosthetic heme groups upon oxidation. This produces metabolically active that is exchangeable between acceptor proteins, macromolecules and low molecular weight ligands, termed here labile heme. As it accumulates in plasma acts pro-oxidant manner regulates cellular metabolism while exerting pro-inflammatory cytotoxic effects foster the pathogenesis hemolytic diseases. Here, we developed characterized panel heme-specific...
The effect of increasing pL on the extraordinary catalytic activity a dinuclear Zn2+ complex toward cleavage uridine 3'-4-nitrophenyl phosphate (UpPNP) in H2O and D2O was determined. This change from to causes an increase 7.8 8.4 apparent pKa functional group, but has little active form catalyst UpPNP, so that there is no primary kinetic SDIE reaction movement proton at rate-determining transition state. It concluded essentially all rate acceleration for this due electrostatic stabilization...
The use of de novo designed peptides is a powerful strategy to elucidate Hg(II)-protein interactions and gain insight into the chemistry Hg(II) in biological systems. Cysteine derivatives alpha-helical TRI family [Ac-G-(L(a)K(b)A(c)L(d)E(e)E(f)K(g))(4)-G-NH(2)] bind at high pH values peptide/Hg(II) ratios 3:1 with an unusual trigonal thiolate coordination mode. resulting complexes are good water-soluble models for binding protein MerR. We have carried out parallel study using (199)Hg NMR...
The cyclization of 2-(hydroxypropyl)-4-nitrophenyl phosphate (HpPNP) catalyzed by the dinuclear zinc complex 1,3-bis(1,4,7-triazacyclonon-1-yl)-2-hydroxypropane (1) proceeds a transition state that is different from uncatalyzed reaction. Kinetic isotope effects (KIEs) measured in nucleophilic atom and leaving group show has (TS) with little phosphorus−oxygen bond fission to (18klg = 1.0064 ± 0.0009 15k 1.0002 0.0002) formation occurs rate-determining step (18knuc 1.0326 0.0008). In reaction,...
The emergence of superbugs developing resistance to antibiotics and the resurgence microbial infections have led scientists start an antimicrobial arms race. In this context, we previously identified active RiPP, Ruminococcin C1, naturally produced by Ruminococcus gnavus E1, a symbiont healthy human intestinal microbiota. This subclassified as sactipeptide, requires host digestive system become against pathogenic Clostridia multidrug-resistant strains. Here report its unique compact...
Dinuclear Cd(II), Cu(II), and Zn(II) complexes of L2OH (L2OH = 1,3-bis(1,4,7-triazacyclonon-1-yl)-2-hydroxypropane) are compared as catalysts for cleavage the RNA analogue HpPNP (HpPNP 2-hydroxypropyl 4-nitrophenyl phosphate) at 25 degrees C, I 0.10 M (NaNO(3)). Cu(II) readily form dinuclear millimolar concentrations a 2:1 ratio metal ion to neutral pH. The Zn(2)(L2O) Cu(2)(L2O) have bridging alkoxide group that brings together two cations in close proximity facilitate cooperative catalysis....
Advances in protein chemistry and molecular structural biology have empowered modern chemists to build complex biological architectures using a "first principles" approach, which is known as de novo design. In this Perspective we demonstrate how simple three-stranded alpha-helical constructs can be prepared by the sole consideration of primary amino acid sequence peptide. With these well defined systems, then that metal binding cavities carved out hydrophobic cores aggregates order bind ions...
The purposes of this study were the development and preclinical evaluation clinically translatable E-selectin-specific ultrasound contrast agents based on a peptide ligand with recognition sequence IELLQAR.The was synthesized through solid phase synthesis covalently attached to poly n-butylcyanoacrylate-stabilized microbubbles an air core. Quantification microbubble surface coverage peptides performed flow cytometry. Targeted adhesion peptide-coated investigated in vitro using parallel plate...
Abstract Water oxidation by copper‐based complexes to form dioxygen has attracted attention in recent years, with the aim of developing efficient and cheap catalysts for chemical energy storage. In addition, high‐valent metal–oxo species produced metal presence water can be used achieve substrate oxygenation use H 2 O as an oxygen source. To date, this strategy not been reported copper complexes. Herein, a copper(II) complex, [(RPY2)Cu(OTf) ] (RPY2=N‐substituted bis[2‐pyridyl(ethylamine)]...
Molecular recognition and control of the physical properties metal ions are major challenges in metalloprotein design. The newly designed peptide Grand L16PenL26AL30C binds two CdII ions, each with a different coordination geometry—trigonal planar or pseudotetrahedral (see picture; Cd purple, S yellow, O blue). centers, such as site selectivity pH dependence binding, differ well.
Abstract The powerful combination of 113 Cd NMR and 111m PAC (perturbed angular correlation) spectroscopies has been critical to determine the coordination geometry II bound thiolate‐rich centers. We have obtained important linear correlations between spectroscopic data acid/base properties metal binding site that illustrate presence a dynamic model for (see figure). These unique results can give new insight into ‐substituted Zn proteins. magnified image used as probe zinc metalloenzymes...
Herein we report how de novo designed peptides can be used to investigate whether the position of a metal site along linear sequence that folds into three-stranded α-helical coiled coil defines physical properties Cd(II) ions in either CdS3 or CdS3O (O-being an exogenous water molecule) coordination environments. Peptides are presented bind two identical sites located at different topological positions interior these constructs. The peptide GRANDL16PenL19IL23PenL26I binds as trigonal planar...
Abstract Designing small peptides that are capable of binding Cu 2+ ions mainly through the side‐chain functionalities is a hard task because amide nitrogen atoms strongly compete for ion coordination. However, design such important obtaining biomimetic systems metalloenyzmes as well development artificial systems. With this in mind, cyclic decapeptide, C‐Asp, which contained three His residues and one Asp residue, its linear derivative, O‐Asp, were synthesized. The C‐Asp peptide has two...
A four amino acid peptide containing the β-turn template dPro-Pro in middle and two cysteines (Cys) terminal positions (CdPPC) has been synthesized its mercury(II) coordination properties studied using different spectroscopic methods. The UV–vis, CD, 199mHg PAC, Raman studies indicate binding of HgII to Cys, forming dithiolatemercury(II) complex Hg(CdPPC). Electrospray ionization mass spectrometry corroborates 1:1 formation. log K = 40.0 was determined for formation constant Hg(CdPPC)...