Publications associées à Lipid polymorphism

Simultaneous Electrophysiology and Imaging Reveal Changes in Lipid Membrane Thickness and Tension upon Uptake of Amphiphilic Gold Nanoparticles

Francesco Stellacci, Xufeng Xu, Paulo Henrique Jacob Silva, Camilla Servidio

Amphiphilic gold core nanoparticles (AmNPs) striped with hydrophilic 11-mercapto-1-undecanesulfonate (MUS) and hydrophobic 1-octanethiol (OT) ligands are promising candidates for drug carriers that passively and nondisruptively enter cells. Yet, how they i ...

Amer Chemical Soc2023

Effects of thermal, mechanical, and electrostatic perturbations on lipid membrane hydration investigated by second harmonic imaging

Seonwoo Lee

Hydrated lipid bilayer membranes are crucial components of cells and organelles, serving as the outer boundary that separates the cellular components from the extracellular environment. Lipid membranes regulate their structures and functions by dynamically ...

EPFL2023

Mitochondrial respiratory chain dysfunction disrupts intracellular cholesterol homeostasis

Christopher Tadhg James Wall

Mitochondrial diseases are rare and severe conditions with debilitating symptoms. Biochemical defects in mitochondria however are common. The difference between these two frequencies is suspected to lie in the capability of the cells to adapt to the homeos ...

EPFL2022

Molecular ordering effects in bulk and at lipid/water nanoscopic interfaces: A story of water, light, and order

Nathan Dupertuis

Water is ubiquitous on Earth, playing a critical role for a plethora of structures, processes and chemical reactions in nature. Its unique physicochemical properties originate mainly from its hydrogen bond network. Despite its recognized importance, many a ...

EPFL2021

Asymmetric opening of the homopentameric 5-HT3A serotonin receptor in lipid bilayers

Horst Vogel, Shuguang Yuan

Pentameric ligand-gated ion channels (pLGICs) of the Cys-loop receptor family are key players in fast signal transduction throughout the nervous system. They have been shown to be modulated by the lipid environment, however the underlying mechanism is not ...

Nature Research2021

3D reconstruction of weakly scattering objects from 2D intensity-only measurements using the Wolf transform

Demetri Psaltis, Joowon Lim, Elizabeth Elena Antoine, Ahmed Ayoub

A new approach to optical diffraction tomography (ODT) based on intensity measurements is presented. By applying the Wolf transform directly to intensity measurements, we observed unexpected behavior in the 3D reconstruction of the sample. Such a reconstru ...

2021

Nematic Ordering of Anisotropic Nanoparticles in Block Copolymers

Ignacio Pagonabarraga Mora

Block copolymer melts have been previously used to control the position and alignment of anisotropic nanoparticles. In this work, 2D and 3D mesoscopic simulations are used to explore the phase behavior of block copolymer/nanoparticle systems. The method co ...

WILEY-V C H VERLAG GMBH2021

Transient domains of ordered water induced by divalent ions lead to lipid membrane curvature fluctuations

Sylvie Roke, Orly Bagunu Tarun, Halil Ibrahim Okur

Cations influence the electrostatic, chemical and mechanical properties of lipid bilayers. Here, label-free second harmonic microscopy shows that cation-induced transient ordering of water also plays a role in driving membrane curvature fluctuations, linki ...

NATURE PUBLISHING GROUP2020

Soft matter probed by nonlinear scattering: self-assembly, interfaces, hydration, and long-range order

Jan Dedic

All organisms are made to a large extent of soft matter - macromolecules such as proteins and polysaccharides, or assemblies of small molecules such as lipids embedded in an aqueous environment. Understanding the role of order in soft matter presents a cha ...

EPFL2020

Dynamic Imaging of Lipid Membranes by Means of Water

Orly Bagunu Tarun

Lipid membranes are self-assembled structures whose composition determines the properties of membranes of cells and organelles. The molecular level understanding of lipid membranes is based on spectroscopy and MD simulations of lipid monolayer systems. As ...

EPFL2019

Dissipative particle dynamics simulations of tri-block co-polymer and water: Phase diagram validation and microstructure identification

Ignacio Pagonabarraga Mora

In this study, the phase diagram of Pluronic L64 and water is simulated via dissipative particle dynamics (DPD). The peculiar structures that form when the concentration varies from dilute to dense (i.e., spherical and rod-like micelles, hexagonal and lame ...

2018

Label-free and charge-sensitive dynamic imaging of lipid membrane hydration on millisecond time scales

Sylvie Roke, Orly Bagunu Tarun

Biological membranes are highly dynamic and complex lipid bilayers, responsible for the fate of living cells. To achieve this function, the hydrating environment is crucial. However, membrane imaging typically neglects water, focusing on the insertion of p ...

2018

Monitoring Membrane Lipidome Turnover by Metabolic N-15 Labeling and Shotgun Ultra-High-Resolution Orbitrap Fourier Transform Mass Spectrometry

Yury Tsybin, Konstantin Nagornov, Kristina Srzentic

Lipidomes undergo permanent extensive remodeling, but how the turnover rate differs between lipid classes and molecular species is poorly understood. We employed metabolic N-15 labeling and shotgun ultra-high-resolution mass spectrometry (sUHR) to quantify ...

Amer Chemical Soc2017

Interfacial Structure and Hydration of 3D Lipid Monolayers in Aqueous Solution

Sylvie Roke, Yixing Chen, Halil Ibrahim Okur, Nikolay Smolentsev, Evangelia Zdrali

Three-dimensional (3D) phospholipid monolayers at hydrophobic surfaces are ubiquitous and found in nature as adiposome organelles or in man-made materials such as drug delivery systems. However, the molecular level understanding of such monolayers remains ...

American Chemical Society2017

Pre-transition effects mediate forces of assembly between transmembrane proteins

Berend Smit

We present a mechanism for a generic, powerful force of assembly and mobility for transmembrane proteins in lipid bilayers. This force is a pre-transition (or pre-melting) effect for the first-order transition between ordered and disordered phases in the m ...

Elife Sciences Publications Ltd2016

Intermolecular Headgroup Interaction and Hydration as Driving Forces for Lipid Transmembrane Asymmetry

Sylvie Roke, Halil Ibrahim Okur, Nikolay Smolentsev, Cornelis Ulrich Lütgebaucks

Variations between the inner and outer leaflets of cell membranes are crucial for cell functioning and signaling, drug–membrane interactions, and the formation of lipid domains. Transmembrane asymmetry can in principle be comprised of an asymmetric charge ...

American Chemical Society2016

The effects of globotriaosylceramide tail saturation level on bilayer phases

Julian Charles Shillcock

Globotriaosylceramide (Gb(3)) is a glycosphingolipid present in the plasma membrane that is the natural receptor of the bacterial Shiga toxin. The unsaturation level of Gb(3) acyl chains has a drastic impact on lipid bilayer properties and phase behaviour, ...

Royal Soc Chemistry2015

Crystalline Oligo(ethylene sulfide) Domains Define Highly Stable Supramolecular Block Copolymer Assemblies

Jeffrey Alan Hubbell, Davide Demurtas, Edward Allen Phelps, Carrie Ellen Brubaker

With proper control over copolymer design and solvation conditions, self-assembled materials display impressive morphological variety that encompasses nanoscale colloids as well as bulk three-dimensional architectures. Here we take advantage of both hydrop ...

Amer Chemical Soc2015

Novel Chemosensors for Biologically Important Analytes

Ziya Köstereli

In this work, fluorescent-based chemosensors for the detection of important analytes in aqueous solution are described. The sensors are based on different detection concepts, including analyte-induced aggregation/de-aggregation, pattern-based sensing and m ...

EPFL2015

Pattern-based sensing of aminoglycosides with fluorescent amphiphiles

Rosario Scopelliti, Kay Severin, Ziya Köstereli

A mixture of two amphiphiles with fluorescent head groups can be used as a sensing ensemble for the pattern-based analysis of aminoglycoside antibiotics. In buffered aqueous solution, the amphiphiles form a dynamic mixture of micellar aggregates. In the pr ...

Royal Soc Chemistry2014