Aims:  To investigate the major microorganisms, which were isolated from internal organs, related to tetrodotoxin (TTX)-accumulation of puffer fish Lagocephalus lunaris. Methods and Results:  Puffer fish Lagocephalus lunaris around Chang Island in the Gulf of Thailand were collected to examine TTX-accumulation and microbial load in internal organs. The nine predominant ...

Under cold acclimated conditions, goldfish (Carassius auratus) express an interlamellar cell mass (ILCM) which limits diffusive ion loss but may also impede branchial ammonia excretion (J(amm)). In the present study, goldfish were subjected to a 2-week 5 or 25°C acclimation in order to modulate the degree of ILCM gill coverage ...

Atg8 is a ubiquitin-like protein required for autophagy in the budding yeast Saccharomyces cerevisiae. A ubiquitin-like system mediates the conjugation of the C terminus of Atg8 to the lipid phosphatidylethanolamine (PE), and this conjugate (Atg8-PE) plays a crucial role in autophagosome formation at the pre-autophagosomal structure (PAS). The cysteine protease ...

The synthesis of reproducible and continuous AlPO-18 membranes is demonstrated. The separation performance of these membranes for equimolar CO(2)/CH(4) gas mixtures is presented. The AlPO-18 membranes displayed CO(2) permeances as high as ∼6.6 × 10(-8) mol m(-2) s Pa with CO(2)/CH(4) separation selectivities in the ∼52-60 range at 295 K ...

The degradation of polyamide (PA) nanofiltration and reverse osmosis membranes by chlorine needs to be understood in order to develop chlorine-resistant membranes. Coated and uncoated fully aromatic (FA) and piperazine (PIP) semi-aromatic PA membranes were treated with hypochlorite solution and analyzed by X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared ...

Phosphatidate (PA) phosphatase, the enzyme that catalyzes the penultimate step in triacylglycerol synthesis, is a cytosolic enzyme that must associate with the membrane where its substrate PA resides. Fluorescence spectroscopy was used to measure the interaction of yeast PAH1-encoded PA phosphatase with model liposome membranes. PA phosphatase contains five tryptophan ...

We studied the interaction of cytochrome c (cyt c) with specific calixarenes (CX) incorporated into the large unilamellar vesicles (LUV) composed of dimyristoylphosphatidylcholine (DMPC) or supported lipid membranes (sBLM) and compared this with not specific adsorption of cyt c to the LUV containing DMPC and anionic phosphatidic acid (PA) or ...

The agent of Lyme disease, Borrelia burgdorferi, has a number of outer membrane proteins that are differentially regulated during its life-cycle. In addition to their physiological functions in the organism, these proteins also likely serve different functions in invasiveness and immune evasion. In the case of the Borreliae, as well ...

Electroless deposition was used to coat porous alumina membranes with gold. This process reduced the pore diameters and provided a platform suitable for surface modifications with self assembled monolayers (SAMs). The surface enhanced Raman scattering (SERS) effect was employed in order to confirm and characterise the formation of SAMs of ...

Purpose: The purpose of this study is to apply photoacoustic imaging (PAI) to monitor high intensity focused ultrasound (HIFU) process in real-time for accurate evaluation of thermal ablation outcomes.Methods: A photoacoustic (PA) imaging system was used to monitor HIFU ablation process in this study. Single-element, spherically focused ultrasonic transducers with ...

PURPOSE:: To examine the relative changes in diameter and modulus of soft contact lenses when the temperature is raised from room temperature (RT) to eye temperature (ET). METHODS:: Thirteen lens types including 9 silicone hydrogel lenses were measured for diameter and elastic modulus at RT (20 ± 1°C) and ET ...

A series of the N-substituted polyaspartamides possessing repeating aminoethylene units in the side chain was prepared in this study to identify polyplexes with effective endosomal escape and low cytotoxicity. All cationic N-substituted polyaspartamides showed appreciably lower cytotoxicity than that of commercial transfection reagents. Interestingly, a distinctive odd-even effect of the ...

A single-chip electrochemical method based on impedance measurements in resonance mode has been employed to study lipid monolayer and bilayer formation on hydrophobic alkanethiolate and SiO2 substrates, respectively. The processes were monitored by temporally resolving changes in interfacial capacitance and resistance, revealing information about the rate of formation, coverage and ...

Infantile neuroaxonal dystrophy (INAD) is a fatal neurodegenerative disease characterized by the widespread presence of axonal swellings (spheroids) in the CNS and PNS and is caused by gene abnormality in PLA2G6 [calcium-independent phospholipase A(2)β (iPLA(2)β)], which is essential for remodeling of membrane phospholipids. To clarify the pathomechanism of INAD, we ...

We report on the first systematic study of spin transport in bilayer graphene (BLG) as a function of mobility, minimum conductivity, charge density, and temperature. The spin-relaxation time τ_{s} scales inversely with the mobility μ of BLG samples both at room temperature (RT) and at low temperature (LT). This indicates ...

Low-temperature vacuum reduction was used for the preparation of the oxygen-deficient BiMnO(2.81) sample in a bulk form from stoichiometric BiMnO(3). The transformation occurs in vacuum better than 10(-3) Pa at a narrow temperature range of 570-600 K. The structure of the new phase was analyzed using synchrotron X-ray powder diffraction ...

Phospholipid headgroups act as major determinants in proper folding of oligomeric membrane proteins. The K(+)-channel KcsA is the most popular model protein among these complexes. The presence of zwitterionic nonbilayer lipid phosphatidylethanolamine (PE) is crucial for efficient tetramerization and stabilization of KcsA in a lipid bilayer. In this study, the ...

Surfactant amphiphilic macromolecules (AMs) were complexed with a 1:1 ratio of 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) and 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE), either by a coevaporation (CE) or postaddition (PA) method, to form AM-lipid complexes with enhanced drug delivery applications. By characterizing the surfactant-lipid interactions, these heterogeneous drug delivery systems can be better controlled and engineered ...

Confluence of a modular design approach and self-assembly with a 'steroid-D-π-A' module generates spontaneous polarization in solids and for the first time in nano-architectures constituted from organogels, at room temperature (RT).

Mixtures of ceramides with other lipids in the presence of water are key components of the structure of the lipid matrix of the stratum corneum and are involved in lateral phase separation processes occurring in lipid membranes. Besides their structural role, ceramides are functional for cell signaling and trafficking. We ...

Genistein modified poly(amide):poly(vinyl pyrrolidone) (PA:PVP/G) hemodialysis membranes have been fabricated by coagulation via solvent (dimethyl sulfoxide, DMSO)/non-solvent (water) exchange. The anti-oxidant and anti-inflammatory properties of the unmodified PA:PVP membranes were evaluated in vitro using human blood. It was found that these unmodified PA:PVP membranes were non-cytotoxic to peripheral blood mononuclear ...

Nimesulide (NIM), a widely used nonsteroidal anti-inflammatory drug (NSAID), is known to interfere with mitochondrial physiology and to cause idiosyncratic hepatotoxicity. In this study, we characterized the effects of NIM on the physical properties of membrane models containing the main phospholipid classes of the inner mitochondrial membrane: phosphatidylcholine (PC), phosphatidylethanolamine ...

FCCP (carbonylcyanide p-trifluoromethoxyphenylhydrazone), a classical uncoupler of mitochondrial oxidative phosphorylation, is used in this study as a model to clarify how interactions of uncouplers with membrane lipid bilayers may influence membrane biophysics and their protonophoric activity itself. In order to disclose putative effects that may be important when considering using ...

Differential scanning calorimetry (DSC) was used to study the miscibility of phosphatidic acids (PAs) with phosphatidylethanolamines (PEs) as a function of chain length (n = 14, 16) and degree of ionization of PAs at pH 4, pH 7, and pH 12. Phase diagrams were constructed using temperature data for onset and end ...

The lysis cassette of Pseudomonas aeruginosa phage ϕKMV encodes a holin, endolysin, Rz and Rz1 in the canonical order. It has a tight organization with a high degree of overlapping genes and is highly conserved (between 96 and 100% identity at the protein level) among several other members of the ...

Efficient membrane fusion has been successfully mimicked in vitro using artificial membranes and a number of cellular proteins that are currently known to participate in membrane fusion. However, these proteins are not sufficient to promote efficient fusion between biological membranes, indicating that critical fusogenic factors remain unidentified. We have recently ...

The aim of our study was to investigate the association of desmosomal proteins with cholesterol-enriched membrane domains, commonly called membrane rafts, and the influence of cholesterol on desmosome assembly in epithelial Madin-Darby canine kidney cells (clone MDc-2). Biochemical analysis proved an association of desmosomal cadherin desmocollin 2 (Dsc2) in cholesterol-enriched ...

Sphingomyelin (SM), a major lipid constituent of outer leaflet of plasma membranes, with cholesterol, constitutes microdomains, which are termed as lipid rafts. These rafts provide support to proteins, receptors, enzymes, and so on and organize and orient them to conduct cellular functions including transmembrane signaling to substances in external milieu. ...

Partitioning of membrane proteins into various types of microdomains is crucial for many cellular functions. Tetraspanin-enriched microdomains (TEMs) are a unique type of protein-based microdomain, clearly distinct from membrane rafts, and important for several cellular processes such as fusion, migration and signaling. Paradoxically, HIV-1 assembly/egress occurs at TEMs, yet the ...

Since the discovery of cellular membrane rafts, the defining of these domains has remained ambiguous due to a great number of isolation procedures proposed for the extraction of the rafts from cells. Characterization of membrane rafts using Triton X-100 insolubility is limited by the fact that weak interactions between proteins ...

Evidence is emerging that tissue-factor-bearing microparticles and other microparticles arise from regions of the parent cell's plasma membrane that are rich in lipid rafts. In this brief review, we summarize the evidence for the raft origins of microparticles and the implications of these origins for the biological and medical consequences ...

Lipid domains in mammalian plasma membranes serve as platforms for specific recruitment or separation of proteins involved in various functions. Here, we have applied this natural strategy of lateral separation to functionalize lipid membranes at micrometer scale in a switchable and reversible manner. Membrane-anchored peptide nucleic acid and DNA, differing ...

The plasma membrane has been hypothesized to contain nanoscopic lipid platforms, which are discussed in the context of "lipid rafts" or "membrane rafts." Based on biochemical and cell biological studies, rafts are believed to play a crucial role in many signaling processes. However, there is currently not much information on ...

Protein sorting and assembly in membrane biogenesis and function involves the creation of ordered domains of lipids known as membrane rafts. The rafts are comprised of all the major classes of lipids, including glycerophospholipids, sphingolipids and sterol. Cholesterol is known to interact with sphingomyelin to form a liquid-ordered bilayer phase. ...

The plant sucrose transporter SUT1 (from Solanum tuberosum, S. lycopersicum, or Zea mays) exhibits redox-dependent dimerization and targeting if heterologously expressed in S. cerevisiae (Krügel et al., 2008). It was also shown that SUT1 is present in motile vesicles when expressed in tobacco cells and that its targeting to the ...

Ten years ago, we wrote a Review on lipid rafts and signalling in the launch issue of Nature Reviews Molecular Cell Biology. At the time, this field was suffering from ambiguous methodology and imprecise nomenclature. Now, new techniques are deepening our insight into the dynamics of membrane organization. Here, we ...

Although the conjugated linoleic acids (CLA) have several isomer-specific biological effects including anti-carcinogenic and anti-adipogenic effects, their mechanisms of action remain unclear. To determine their potential effects on membrane structure and function, we studied the incorporation profiles of four CLA isomers (trans-10 cis-12 (A), trans-9 trans-11 (B), cis-9 trans-11 (C), ...

Cholesterol is believed to be an important component in compositionally distinct lipid domains in the cellular plasma membrane, which are referred to as lipid rafts. Insight into how cholesterol influences the interactions that contribute to plasma membrane organization can be acquired from model lipid membranes. Here we characterize the lipid ...

Background. Sphingomyelin (SM), a major lipid constituent of outer leaflet of plasma membranes, with cholesterol, constitutes microdomains, which are termed as lipid rafts. These rafts provide support to proteins, receptors, enzymes, and so on and organize and orient them to conduct cellular functions including transmembrane signaling to substances in external ...

BCR-mediated Ag processing and presentation is critical to the initiation and control of a humoral immune response. Trafficking of internalized Ag-BCR complexes to intracellular Ag processing compartments is driven by ubiquitination of the cytoplasmic domain of the BCR. Using a biochemical approach, it is here established that ubiquitinated Ag-BCR complexes ...

We argue that membrane viscosity, η(m), plays a prominent role in the thermal fluctuation dynamics of micron-scale lipid domains. A theoretical expression is presented for the timescales of domain shape relaxation, which reduces to the well-known η(m) = 0 result of Stone and McConnell in the limit of large domain ...

The detergent (Triton X-100, 4°C)-resistant membrane (DRM)-associated membrane proteins stomatin, sorcin, and synexin (anexin VII) exposed on the cytoplasmic side of membrane were investigated for their lateral distribution in relation to induced ganglioside(M1) (GM1) raft patches in flat (discocytic) and curved (echinocytic) human erythrocyte membrane. In discocytes, no accumulation of ...

The effect of temperature on the surface phase behavior of tetradecanoyl N-ethanolamide (NHEA-14) in Langmuir monolayers at the air-water interface has been investigated by film balance and Brewster angle microscopy (BAM). It has been observed that dendritic domains are formed in the coexistence region between liquid-expanded (LE) and liquid-condensed (LC) ...

We show that highly efficient depletion of sphingolipids in two different cell lines does not abrogate the ability to isolate Lubrol-based DRMs (detergent-resistant membranes) or detergent-free lipid rafts from these cells. Compared with control, DRM/detergent-free lipid raft fractions contain equal amounts of protein, cholesterol and phospholipid, whereas the classical DRM/lipid ...

Membrane rafts are sphingolipid- and cholesterol-rich microdomains that contain dynamic arrangements of signaling proteins. Notably, various components of the ubiquitous cAMP/Protein Kinase A (PKA) pathway, including β-adrenergic receptors (β-ARs), G proteins, and adenylyl cyclases (ACs), have been shown to localize differentially between membrane rafts and non-raft regions of the plasma ...

Phage holins are small, lethal membrane proteins of two general types: canonical holins, like λ S105, which oligomerizes and forms large membrane holes of unprecedented size; and pinholins, like S(21) 68 of lambdoid phage 21, which forms homo-heptameric channels, or pinholes, with a lumen of <2 nm. Pinholes depolarize the ...

The nicotinic acetylcholine receptor (AChR) is in intimate contact with the lipids in its native membrane. Here we analyze the possibility that it is the intrinsic properties of the AChR that determine its partition into a given lipid domain. Torpedo AChR or a synthetic peptide corresponding to the AChR M4 ...

The membranes of eukaryotic cells harbor microdomains known as lipid rafts that contain a variety of signaling and transport proteins. Here we show that bacterial membranes contain microdomains functionally similar to those of eukaryotic cells. These membrane microdomains from diverse bacteria harbor homologs of Flotillin-1, a eukaryotic protein found exclusively ...

Thermosensors are ubiquitous integral membrane proteins found in all kinds of life. They are involved in many physiological roles, including membrane remodeling, chemotaxis, touch, and pain [1-3], but, the mechanism by which their transmembrane (TM) domains transmit temperature signals is largely unknown. The histidine kinase DesK from Bacillus subtilis is ...

The effect of cholesterol (CHOL) on the material properties of supported lipid bilayers composed of lipid mixtures that mimic the composition of lipid microdomains was studied by force-volume (FV) imaging under near-physiological conditions. These studies were carried out with lipid mixtures of dioleoylphosphatidylcholine, dioleoylphosphatidylserine, and sphingomyelin. FV imaging enabled simultaneous ...