Measurement of phospholipid lateral diffusion at high pressure by in situ magic-angle spinning NMR spectroscopy

Communications Chemistry, Journal Year: 2025, Volume and Issue: 8(1)

Published: Feb. 14, 2025

The development of experimental methodologies that enable investigations biochemistry at high pressure promises to yield significant advances in our understanding life on Earth and its origins. Here, we introduce a method for studying lipid membranes thermodynamic conditions relevant deep sea hydrothermal vents. Using situ magic-angle spinning solid state nuclear magnetic resonance spectroscopy (NMR), measure changes the fluidity model microbial pressures up 28 MPa. We find fluid-phase lateral diffusion phospholipids is significantly affected by stoichiometric ratio lipids membrane. Our results were facilitated an accessible pressurization strategy have developed routine preparation NMR rotors 30 MPa or greater.

Language: Английский

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Structural characterization of archaeal GDGT cyclization: Linking physiological adaptation to paleotemperature reconstruction

Earth and Planetary Science Letters, Journal Year: 2025, Volume and Issue: 657, P. 119293 - 119293

Published: March 5, 2025

Language: Английский

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Restricted Surface Diffusion of Cytochromes on Bioenergetic Membranes with Anionic Lipids

Membranes, Journal Year: 2025, Volume and Issue: 15(4), P. 124 - 124

Published: April 13, 2025

Bioenergetic membranes of mitochondria, thylakoids, and chromatophores are primary sites ATP production in living cells. These contain an electron transport chain (ETC) which electrons shuttled between a series redox proteins during the generation via oxidative phosphorylation. The phospholipid composition these membranes, often include negative lipids, plays role determining electrostatics their surface owing to spatial distribution charged head groups. Cardiolipin (CDL) is commonly associated with bioenergetic also significant contributor charge. Interactions cytochromes groups membrane can principle affect rate its travel ETC components, hence influencing turnover. Here, we use molecular dynamic (MD) simulations that feature accelerated model, termed highly mobile mimetic (HMMM), study protein–lipid interactions diffusion cytochrome c2 partners membrane. We observe “skipping” mode for along bias binding anionic particularly strong preference CDL. During diffusion, maintains relatively fixed tilt respect normal wider fluctuations angle plane obtained results describing behavior on representative have direct ramifications shuttling motions other similar electron-carrying elements composed amount lipids. surface-restricted reported here would modulate rapid transfer complexes anchored by reducing search space them.

Language: Английский

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Quantifying Ionic Liquid Affinity and Its Effect on Phospholipid Membrane Structure and Dynamics

Langmuir, Journal Year: 2025, Volume and Issue: unknown

Published: May 1, 2025

Understanding the interactions between ionic liquids (ILs) and biomembranes is pivotal for uncovering origins of IL-induced biological activities their potential applications in pharmaceuticals. In this study, we investigate influence imidazolium-based ILs on viscoelasticity, dynamics, phase behavior two model membrane systems: (i) lipid monolayers (ii) unilamellar vesicles, both composed dipalmitoylphosphatidylcholine (DPPC). Two different with varying alkyl chain lengths, namely, 1-decyl-3-methylimidazolium bromide (DMIM[Br]) 1-hexyl-3-methylimidazolium (HMIM[Br]) are used to role lengths. Our findings demonstrate that induce significant disorder membranes by altering area per molecule, thereby modulating viscoelastic properties. a longer show stronger membranes, causing more pronounced disorder. Fourier transform infrared spectroscopy indicates IL incorporation shifts membrane's main transition lower temperatures introduces gauche defects, signifying increased structural This effect amplified chains higher concentrations. Quasielastic neutron scattering studies highlight markedly enhance lateral diffusion lipids within leaflet, extent enhancement determined physical state, concentration, length. The most acceleration occurs ordered concentrations longer-chain IL. Molecular dynamics simulations corroborate these experimental findings, showing extensively disrupt organization, introduce increase lipid, consequently diffusion. fluidity permeability provides mechanistic basis observed toxicity associated ILs. These results offer critical insights into molecular-level advancing our understanding toxicological pharmaceutical implications.

Language: Английский

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Atherosclerotic Oxidized Lipids Affect Formation and Biophysical Properties of Supported Lipid Bilayers and Simulated Membranes

The Journal of Physical Chemistry B, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 18, 2024

Oxidized lipids arising from oxidative stress are associated with many serious health conditions, including cardiovascular diseases. For example, KDdiA-PC and KOdiA-PC two oxidized phosphatidylcholines (oxPC) directly linked to atherosclerosis, which precipitate heart failure, stroke, aneurysms, chronic kidney disease. These oxPCs well-characterized in small particles such as low-density lipoprotein, but how their presence affects the biophysical properties of larger bilayer membranes is unclear. It also unclear membrane mediators, cholesterol, affect lipid bilayers containing these oxPCs. Here, we characterize supported (SLBs) POPC, KDdiA-PC, or KOdiA-PC, cholesterol. We used a quartz crystal microbalance dissipation monitoring (QCM-D), fluorescence microscopy, all-atom molecular dynamics (MD) examine formation process, properties, specific conformations simulated bilayers. Experimentally, show that liposomes either oxPC form SLBs by rupturing on contact SiO2 substrates, differs typical adsorption-rupture pathway observed nonoxidized liposomes. increasing concentration results thinner contain defects. Simulations reveal sn-2 tails bend out hydrophobic core into hydrophilic headgroup region beyond. The altered oxPC, affected cholesterol content protonation state functional groups, contribute trends decreasing thickness area concentration. This combined approach provides comprehensive view at level, crucial understanding role oxidation disease related immune responses.

Language: Английский

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Molecular dynamics insight of interaction between Artemisinin and its derivatives and the cancer cell membrane

Computational and Theoretical Chemistry, Journal Year: 2024, Volume and Issue: unknown, P. 114997 - 114997

Published: Nov. 1, 2024

Language: Английский

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