Non-Polar Lipids as Regulators of Membrane Properties in Archaeal Lipid Bilayer Mimics

The modification of archaeal lipid bilayer properties by the insertion of apolar molecules in the lipid bilayer midplane has been proposed to support cell membrane adaptation to extreme environmental conditions of temperature and hydrostatic pressure. In this work, we characterize the insertion effects of the apolar polyisoprenoid squalane on the permeability and fluidity of archaeal model membrane bilayers, composed of lipid analogues. We have monitored large molecule and proton permeability and Laurdan generalized polarization from lipid vesicles as a function of temperature and hydrostatic pressure. Even at low concentration, squalane (1 mol%) is able to enhance solute permeation by increasing membrane fluidity, but at the same time, to decrease proton permeability of the lipid bilayer. The squalane physicochemical impact on membrane properties are congruent with a possible role of apolar intercalants on the adaptation of Archaea to extreme conditions. In addition, such intercalant might be used to cheaply create or modify chemically resistant liposomes (archeaosomes) for drug delivery.

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Stripping Material from a Supported Lipid Bilayer with High Speed Buffer Flow

American Journal of Undergraduate Research ◽

10.33697/ajur.2020.027 ◽

2020 ◽

Vol 17 (3) ◽

pp. 51-59

Author(s):

Michael Ornstead ◽

Ruth Hunter ◽

Mason Valentine ◽

Cameron Cooper ◽

Stephen Smith ◽

...

Keyword(s):

Lipid Bilayer ◽

Lipid Bilayers ◽

Microfluidic Device ◽

High Speed ◽

Membrane Vesicle ◽

Microfluidic Channel ◽

Lipid Vesicles ◽

Membrane Properties ◽

Supported Lipid Bilayer ◽

Glass Coverslip

A microfluidic device was created and used to demonstrate that supported lipid bilayers can be deposited on clean glass slides and removed using high velocity buffer flow (1-4 m/s linear velocity). This was accomplished by forcing the flow through a microfluidic channel covering an annealed glass coverslip bearing a supported lipid bilayer (SLB). The removal of bilayer material was monitored via fluorescence microscopy, and two basic regimes were observed: at 1-2 m/s smaller areas were stripped, while at 3-4 m/s larger areas were stripped. SLB removal was verified by two means. First, lipid vesicles labeled with a different fluorescent dye were added to the device and filled in holes left by the removal of the original SLB, allowing stripping to be verified visually. Second, the solutions obtained from stripping were concentrated and the fluorescence in the concentrates was measured. The ability to strip SLB from glass provides a relatively gentle method of creating spatially inhomogeneous SLB, which could be a useful tool in the continued investigation of membrane properties and components. KEYWORDS: Supported Lipid Bilayer; Membrane Vesicle; Microfluidic Device

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Role of electromechanical and mechanoelectric effects in protein hydration under hydrostatic pressure

Physical Chemistry Chemical Physics ◽

10.1039/c1cp21819k ◽

2011 ◽

Vol 13 (39) ◽

pp. 17722 ◽

Cited By ~ 10

Author(s):

Irena Danielewicz-Ferchmin ◽

Ewa M. Banachowicz ◽

A. Ryszard Ferchmin

Keyword(s):

Hydrostatic Pressure ◽

Protein Hydration

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The role of orthorhombic distortions in gallium under high hydrostatic pressure

Journal of Physics and Chemistry of Solids ◽

10.1016/j.jpcs.2006.05.016 ◽

2006 ◽

Vol 67 (9-10) ◽

pp. 2132-2135 ◽

Cited By ~ 10

Author(s):

A.S. Mikhaylushkin ◽

S.I. Simak ◽

B. Johansson ◽

U. Häussermann

Keyword(s):

Hydrostatic Pressure ◽

High Hydrostatic Pressure

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Role of nitric oxide in the response of cells to heat shock and high hydrostatic pressure

FEMS Yeast Research ◽

10.1016/s1567-1356(03)00039-4 ◽

2003 ◽

Vol 3 (4) ◽

pp. 341-346 ◽

Cited By ~ 38

Author(s):

T DOMITROVIC ◽

F PALHANO ◽

C BARJAFIDALGO ◽

M DEFREITAS ◽

M ORLANDO ◽

...

Keyword(s):

Nitric Oxide ◽

Hydrostatic Pressure ◽

Heat Shock ◽

High Hydrostatic Pressure

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Possible Role of Extracellular Signal-Regulated Kinase Pathway in Regulation of Sox9 mRNA Expression in Chondrocytes under Hydrostatic Pressure

Journal of Bioscience and Bioengineering ◽

10.1263/jbb.104.506 ◽

2007 ◽

Vol 104 (6) ◽

pp. 506-509 ◽

Cited By ~ 11

Author(s):

Kensuke Mio ◽

Jennifer Kirkham ◽

William A. Bonass

Keyword(s):

Hydrostatic Pressure ◽

Mrna Expression ◽

Extracellular Signal Regulated Kinase ◽

Extracellular Signal ◽

Kinase Pathway

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Of the Movement of Worms

Journal of Experimental Biology ◽

10.1242/jeb.27.1.29 ◽

1950 ◽

Vol 27 (1) ◽

pp. 29-39 ◽

Cited By ~ 2

Author(s):

GARTH CHAPMAN

Keyword(s):

Hydrostatic Pressure ◽

Closed System ◽

Body Fluid ◽

The Body ◽

Cross Sectional ◽

Working Length ◽

Cylindrical Form ◽

Maximum Thrust

Four aspects of the functioning of a fluid-filled cylindrical animal have been examined, viz.: (I) the role of the body fluid as a skeleton for the interaction of the longitudinal and circular muscles of which the animal must be composed; (2) the measurement of the maximum thrust which the animal can exert by measurement of its internal hydrostatic pressure; (3) the application of the force to the substratum and the part played by friction; (4) the relation between the changes in dimensions of the animal and the working length of the muscles. Under (1) the necessity for a longitudinal and circular construction has been shown and the necessity for a closed system emphasized. Under (2) the pressure exerted on the body fluid by the contraction of the longitudinal and circular muscles is discussed, and from their cross-sectional areas it is shown to be probable that when contracting maximally in Lumbricus they are not balanced, but that the longitudinals are about ten times as strong as the circulars. Under (3) it is shown that the strength of an animal as measured by its internal hydrostatic pressure is sufficient to account for its customary activities. Use which may be made of the longitudinals during burrowing is pointed out. Under (4) it is shown to be mechanically sound for burrowing animals of cylindrical form to be ‘fat’, but that a ‘thin’ animal is more efficient at progression.

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Extracellular vesicle interplay in cardiovascular pathophysiology

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00925.2020 ◽

2021 ◽

Author(s):

Sherin Saheera ◽

Vivek P Jani ◽

Kenneth W Witwer ◽

Shelby Kutty

Keyword(s):

Plasma Membrane ◽

Cardiovascular System ◽

Lipid Bilayer ◽

Cellular Responses ◽

Extracellular Vesicle ◽

Cargo Proteins ◽

And Function ◽

Intercellular Communications ◽

Rna And Dna

Extracellular vesicles (EVs) are nanosized lipid bilayer-delimited particles released from cells that mediate intercellular communications and play a pivotal role in various physiological and pathological processes. Subtypes of EVs may include plasma-membrane ectosomes or microvesicles and endosomal-origin exosomes, although functional distinctions remain unclear. EVs carry cargo proteins, nucleic acids (RNA and DNA), lipids, and metabolites. By presenting or transferring this cargo to recipient cells, EVs can trigger cellular responses. Here, we summarize what is known about EV biogenesis, composition, and function, with an emphasis on the role of EVs in cardiovascular system. Additionally, we provide an update on the function of EVs in cardiovascular pathophysiology, further highlighting their potential for diagnostic and therapeutic applications.

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The Impact of O-Glycosylation on Cyanidin Interaction with POPC Membranes: Structure-Activity Relationship

Molecules ◽

10.3390/molecules23112771 ◽

2018 ◽

Vol 23 (11) ◽

pp. 2771

Author(s):

Sylwia Cyboran-Mikołajczyk ◽

Piotr Jurkiewicz ◽

Martin Hof ◽

Halina Kleszczyńska

Keyword(s):

Biological Activity ◽

Free Radicals ◽

Lipid Bilayer ◽

Lipid Membrane ◽

Lipid Vesicles ◽

Structure Activity Relationship ◽

Activity Relationship ◽

Beneficial Effects ◽

Structure Activity ◽

The Impact

Cyanidin and its O-glycosides have many important physiological functions in plants and beneficial effects on human health. Their biological activity is not entirely clear and depends on the structure of the molecule, in particular, on the number and type of sugar substituents. Therefore, in this study the detailed structure-activity relationship (SARs) of the anthocyanins/anthocyanidins in relation to their interactions with lipid bilayer was determined. On the basis of their antioxidant activity and the changes induced by them in size and Zeta potential of lipid vesicles, and mobility and order of lipid acyl chains, the impact of the number and type of sugar substituents on the biological activity of the compounds was evaluated. The obtained results have shown, that 3-O-glycosylation changes the interaction of cyanidin with lipid bilayer entirely. The 3-O-glycosides containing a monosaccharide induces greater changes in physical properties of the lipid membrane than those containing disaccharides. The presence of additional sugar significantly reduces glycoside interaction with model lipid membrane. Furthermore, O-glycosylation alters the ability of cyanidin to scavenge free radicals. This alteration depends on the type of free radicals and the sensitivity of the method used for their determination.

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