References of "Crowet, Jean-Marc"
     in
Bookmark and Share    
See detailFunctional and structural characterisation of the Arabidopsis thaliana HMA4 protein
Lekeux, Gilles ULiege; Laurent, Clémentine; Xiao, Zhiguang et al

Poster (2017, July 24)

Detailed reference viewed: 29 (5 ULiège)
Full Text
Peer Reviewed
See detailStructural Basis for Plant Plasma Membrane Protein Dynamics and Organization into Functional Nanodomains
Gronnier, Julien; Crowet, Jean-Marc ULiege; Habenstein, Birgit et al

in eLife (2017), 6

Plasma Membrane is the primary structure for adjusting to ever changing conditions. PM sub-compartmentalization in domains is thought to orchestrate signalling cascades. Yet, mechanisms governing membrane ... [more ▼]

Plasma Membrane is the primary structure for adjusting to ever changing conditions. PM sub-compartmentalization in domains is thought to orchestrate signalling cascades. Yet, mechanisms governing membrane organization are mostly uncharacterized. The plant-specific proteins REMORINs are factors regulating hormonal crosstalk and host invasion. REMs are the best-characterized PM nanodomain markers targeted to the PM via an uncharacterized moiety called REMORIN C-terminal Anchor. By coupling biophysical methods, super-resolution microscopy and physiology, we decipher an original mechanism regulating the dynamic and organization of nanodomains. We showed that PM targeting is independent of the COP II-dependent secretory pathway and mediated by PI4P and sterol. REM-CA is an unconventional lipid-binding motif that confers nanodomain organization. Analyses of REM-CA mutants by single particle tracking demonstrate that mobility and supramolecular organization are critical for immunity. This study provides a unique mechanistic insight into how the tight control of spatial segregation is critical in the definition of PM domain necessary to support biological function. [less ▲]

Detailed reference viewed: 33 (8 ULiège)
Full Text
Peer Reviewed
See detailDifferential interaction of synthetic glycolipids with biomimetic plasma membrane lipids correlates with plant biological response
Nasir, Mehmet Nail ULiege; Lins, Laurence ULiege; Crowet, Jean-Marc ULiege et al

in Langmuir (2017)

Natural and synthetic amphiphilic molecules including lipopeptides, lipopolysaccharides and glycolipids are able to induce defense mechanisms in plants. In the present work, the perception of two ... [more ▼]

Natural and synthetic amphiphilic molecules including lipopeptides, lipopolysaccharides and glycolipids are able to induce defense mechanisms in plants. In the present work, the perception of two synthetic C14 rhamnolipids, namely Alk-RL and Ac-RL, differing only at the level of the lipid tail terminal group, have been investigated using biological and biophysical approaches. We showed that Alk-RL induces a stronger early signaling response in tobacco cell suspensions than does Ac-RL. The interactions of both synthetic RLs with simplified biomimetic membranes were further analyzed using experimental and in silico approaches. Our results indicate that the interactions of Alk-RL and Ac-RL with lipids were different in terms of insertion and molecular responses and were dependent on the lipid composition of model membranes. A more favorable insertion of Alk-RL than Ac-RL into lipid membranes is observed. Alk-RL forms more stable molecular assemblies than Ac-RL with phospholipids and sterols. At the molecular level, the presence of sterols tends to increase the RLs’ interaction with lipid bilayers with a fluidizing effect on the alkyl chains. Taken together, our findings suggest that the perception of these synthetic RLs at the membrane level could be related to a lipid-driven process depending on the organization of the membrane and the orientation of the RLs within the membrane and is correlated with the induction of early signaling responses in tobacco cells. [less ▲]

Detailed reference viewed: 28 (5 ULiège)
Full Text
Peer Reviewed
See detailMolecular dynamics study of micelle proeprties according to their size
Lebecque, Simon ULiege; Crowet, Jean-Marc ULiege; Nasir, Mehmet Nail ULiege et al

in Journal of Molecular Graphics and Modelling (2017), 72

Surfactants are molecules able to spontaneously self-assemble to form aggregates with well-defined properties, such as spherical micelles, planar bilayers, cylindrical micelles or vesicles. Micelles have ... [more ▼]

Surfactants are molecules able to spontaneously self-assemble to form aggregates with well-defined properties, such as spherical micelles, planar bilayers, cylindrical micelles or vesicles. Micelles have notably several applications in many domains, such as drug delivery or membrane protein solubilization. In this context, the study of micelle formation in relation with the structural and physico-chemical properties of surfactants is of great interest to better control their use in the different application fields. In this work, we use the MD approach developed by Yoshii et al. and extend it to surfactants with different structures. We aim to systematically investigate different micellar properties as a function of the aggregates size by a molecular dynamics approach, to get an insight into the micellar organization and to collect some relevant descriptors about micelle formation. For this, we perform short MD simulations of preformed micelles of various sizes and analyze three parameters for each micelle size, namely the eccentricity of the micelles, the hydrophobic/hydrophilic surface ratio and the hydrophobic tails hydration. If these parameters are known descriptors of micelles, they were not yet studied in this way by MD. We show that eccentricity, used as “validator” parameter, exhibits minimal values when the aggregate size is close to the experimental aggregation number for surfactants that are known to form spherical micelles. This hence indicates that our methodology gives consistent results. The evolution of the two descriptors follows another scheme, with a sharp increase and decrease, respectively, followed by a leveling-off. The aggregate sizes at which this stabilization starts to occur are close to the respective aggregation number of each surfactant. In our approach, we validate the use of these descriptors to follow micelle formation by MD, from “simple” surfactants to more complex structures, like lipopeptides. Our calculations also suggest that some peculiar behavior, like that of TPC, can be highlighted by our approach. In the context of peptidic surfactants, our methodology could further help to improve computer simulations combined to molecular thermodynamic models to predict micellar properties of those more complex amphiphilic molecules. [less ▲]

Detailed reference viewed: 55 (15 ULiège)
Full Text
Peer Reviewed
See detailMembrane Interactions of Natural Cyclic Lipodepsipeptides of the Viscosin Group
Geudens, Niels; Nasir, Mehmet Nail ULiege; Crowet, Jean-Marc ULiege et al

in Biochimica et Biophysica Acta - Biomembranes (2017), 1859(3), 331-339

Many Pseudomonas spp. produce cyclic lipodepsipeptides (CLPs), which, besides their role in biological functions such as motility, biofilm formation and interspecies interactions, are antimicrobial. It ... [more ▼]

Many Pseudomonas spp. produce cyclic lipodepsipeptides (CLPs), which, besides their role in biological functions such as motility, biofilm formation and interspecies interactions, are antimicrobial. It has been established that interaction with the cellular membrane is central to the mode of action of CLPs. In this work, we focus on the CLPs of the so-called viscosin group, aiming to assess the impact of the main structural variations observed within this group on both the antimicrobial activity and the interaction with model membranes. The antimicrobial activity of viscosin, viscosinamide A, WLIP and pseudodesmin A were all tested on a broad panel of mainly Gram-positive bacteria. Their capacity to permeabilize or fuse PG/PE/cardiolipin model membrane vesicles is assessed using fluorescent probes. We find that the Glu2/Gln2 structural variation within the viscosin group is the main factor that influences both the membrane permeabilization properties and the minimum inhibitory concentration of bacterial growth, while the configuration of the Leu5 residue has no apparent effect. The CLPmembrane interactions were further evaluated using CD and FT-IR spectroscopy on model membranes consisting of PG/PE/cardiolipin or POPC with or without cholesterol. In contrast to previous studies, we observe no conformational change upon membrane insertion. The CLPs interact both with the polar heads and aliphatic tails of model membrane systems, altering bilayer fluidity, while cholesterol reduces CLP insertion depth [less ▲]

Detailed reference viewed: 62 (10 ULiège)
Full Text
Peer Reviewed
See detailGROMPALA: a membrane-implicit modelling method to screen lipid-interacting molecules
Steinhauer, Sven; Crowet, Jean-Marc ULiege; Brasseur, Robert ULiege et al

in Mukhametov, Azat (Ed.) Software and techniques for Bio-molecular modeling (2016)

Detailed reference viewed: 90 (5 ULiège)
Full Text
See detailPresentation of the Laboratory of Molecular Biophysics at the Interfaces
Crowet, Jean-Marc ULiege; Nasir, Mehmet Nail ULiege; Deleu, Magali ULiege et al

Conference (2016, April 29)

Detailed reference viewed: 18 (2 ULiège)
Full Text
Peer Reviewed
See detailModeling of the cyclic lipodepsipeptide Pseudodesmin A self-assembly through molecular dynamic simulations
Crowet, Jean-Marc ULiege; Sinnaeve, Davy; Fehér, Kristina et al

Poster (2016, April)

Detailed reference viewed: 19 (0 ULiège)
Full Text
Peer Reviewed
See detailInteractions of sugar-based bolaamphiphiles with biomimetic systems of plasma membranes
Nasir, Mehmet Nail ULiege; Crowet, Jean-Marc ULiege; Lins, Laurence ULiege et al

in Biochimie (2016), 130

Glycolipids constitute a class of molecules with various biological activities. Among them, sugar-based bolaamphiphiles characterized by their biocompatibility, biodegradability and lower toxicity, became ... [more ▼]

Glycolipids constitute a class of molecules with various biological activities. Among them, sugar-based bolaamphiphiles characterized by their biocompatibility, biodegradability and lower toxicity, became interesting for the development of efficient and low cost lipid-based drug delivery systems. Their activity seems to be closely related to their interactions with the lipid components of the plasma membrane of target cells. Despite many works devoted to the chemical synthesis and characterization of sugar-based bolaamphiphiles, their interactions with plasma membrane have not been completely elucidated. In this work, two sugar-based bolaamphiphiles differing only at the level of their sugar residues were chemically synthetized. Their interactions with membranes have been investigated using model membranes containing or not sterol and with in silico approaches. Our findings indicate that the nature of sugar residues has no significant influence for their membrane interacting properties, while the presence of sterol attenuates the interactions of both bolaamphiphiles with the membrane systems. The understanding of this distinct behavior of bolaamphiphiles towards sterol-containing membrane systems could be useful for their applications as drug delivery systems. [less ▲]

Detailed reference viewed: 59 (23 ULiège)
See detailMolecular modelling of the metal ATPase HMA4 from Arabidopsis halleri
Crowet, Jean-Marc ULiege; Lekeux, Gilles ULiege; Hanikenne, Marc ULiege et al

Poster (2015, December 03)

Detailed reference viewed: 18 (3 ULiège)
Full Text
See detailSimulation par dynamique moléculaire de membranes lipidiques complexes
Crowet, Jean-Marc ULiege; Dauchez, Manuel; Lins, Laurence ULiege

Scientific conference (2015, November 25)

Detailed reference viewed: 18 (1 ULiège)
Full Text
Peer Reviewed
See detailModeling of the cyclic lipodepsipeptide Pseudodesmin A self- assembly through molecular dynamic simulations
Crowet, Jean-Marc ULiege; Sinnaeve, Davy; Fehér, Kristina et al

Poster (2015, October)

Detailed reference viewed: 10 (0 ULiège)