The effect of ion binding on the structural, mechanical, dynamic and electrostatic properties of a 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) bilayer in a 0.5 M aqueous NaCl solution is investigated using classical atomistic molecular dynamics simulation with different force-field descriptions for ion-ion and ion-lipid interactions. Most importantly, the repulsive Lennard-Jones par...

The 3D structures of membrane proteins are typically determined without the presence of a lipid bilayer. For the purpose of studying the role of membranes on the wild type characteristics of the corresponding protein, determining the position and orientation of transmembrane proteins within a membrane environment is highly desirable. Here we report a geometry-based approach to automatically ins...

The major permeability barrier in any membrane is the lipid bilayer structure, and its barrier property is inversely correlated with its fluidity. Bacteria cannot make this membrane much less fluid or it will start to interfere with the normal functions of the membrane proteins, so some bacteria have constructed an additional structure that surrounds the cell outside the cytoplasmic membrane. A...

Direct contact of nanoparticles with the plasma membrane is essential for biomedical applications such as intracellular drug delivery and imaging, but the effect of nanoparticle association on membrane structure and function is largely unknown. Here we employ a sensitive electrophysiological method to assess the stability of protein-free membranes in the presence of silica nanospheres of differ...

The membrane of human red blood cells is essentially composed of two parts, the lipid bilayer and the membrane skeleton that interacts with the lipid bilayer. The normal resting shape of the red blood cells at physiological pH 7.4 is the discocyte. However, at alkaline pH approximately equal to 11 the shape of red blood cells is composed of a spherical parent cell and large spherical daughter v...

General anesthetics have revolutionized medicine by facilitating invasive procedures, and have thus become essential drugs. However, detailed understanding of their molecular mechanisms remains elusive. A mechanism proposed over a century ago involving unspecified interactions with the lipid bilayer known as the unitary lipid-based hypothesis of anesthetic action, has been challenged by evidenc...

In this paper, we describe a fabrication method of a glass microfluidic chip for long-term and repeatable lipid bilayer formation. We etched a glass substrate by magnetic neutral loop discharge plasma (NLD) (Fig. 1a). Using this method, we fabricated a glass microfluidic chip with microchambers forming lipid bilayer membranes (Fig.1b,c). Since the glass chip prevents absorption of fluids, the f...

In eukaryotic cells, membranous vesicles and organelles are transported by ensembles of motor proteins. These motors, such as kinesin-1, have been well characterized in vitro as single molecules or as ensembles rigidly attached to nonbiological substrates. However, the collective transport by membrane-anchored motors, that is, motors attached to a fluid lipid bilayer, is poorly understood. Here...

Lipid molecules bound to membrane proteins are resolved in some high-resolution structures of membrane proteins. An analysis of these structures provides a framework within which to analyse the nature of lipid-protein interactions within membranes. Membrane proteins are surrounded by a shell or annulus of lipid molecules, equivalent to the solvent layer surrounding a water-soluble protein. The ...