scholarly journals Self-limiting aggregation of phospholipid vesicles

Soft Matter ◽  
2020 ◽  
Vol 16 (9) ◽  
pp. 2379-2389 ◽  
Author(s):  
N. de Lange ◽  
F. A. M. Leermakers ◽  
J. M. Kleijn
Keyword(s):  
Lipid Vesicles ◽  
Phospholipid Vesicles ◽  
Pair Level

Aggregation of lipid vesicles can be limited to the pair level and is reversible depending on the linker type.

scholarly journals The Lantibiotic Nisin Induces Transmembrane Movement of a Fluorescent Phospholipid

1998 ◽  
Vol 180 (24) ◽  
pp. 6565-6570 ◽  
Author(s):  
Gert N. Moll ◽  
Wil N. Konings ◽  
Arnold J. M. Driessen
Keyword(s):  
Antimicrobial Peptide ◽  
Rate Constant ◽  
Lipid Vesicles ◽  
Phospholipid Vesicles ◽  
Nisin Concentration ◽  
Outer Leaflet ◽  
Target Membrane

ABSTRACT Nisin is a pore-forming antimicrobial peptide. The capacity of nisin to induce transmembrane movement of a fluorescent phospholipid in lipid vesicles was investigated. Unilamellar phospholipid vesicles that contained a fluorescent phospholipid (1-acyl-2-{6-[(7-nitro-2-1,3-benzoxadiazol-4-yl)amino]caproyl}-sn-glycero-3-phosphocholine) in the inner leaflet of the bilayer were used. Nisin-induced movement of the fluorescent phospholipid from the inner leaflet to the outer leaflet of the membrane reached stable levels, which were dependent on the concentration of nisin added. The rate constant k of this nisin-induced transmembrane movement increased with the nisin concentration but was not dependent on temperature within the range of 5 to 30°C. In contrast, the rate constant of movement of fluorescent phospholipid from vesicle to vesicle strongly depended on temperature. The data indicate that nisin transiently disturbs the phospholipid organization of the target membrane.

Modelling the adsorption of phospholipid vesicles to a silicon dioxide surface using Langmuir kinetics

2022 ◽  
Author(s):  
Iad Alhallak ◽  
Peter J. N. Kett
Keyword(s):  
Silicon Dioxide ◽  
Equilibrium Constant ◽  
Rate Constants ◽  
Lipid Vesicles ◽  
Phospholipid Vesicles ◽  
Adsorption And Desorption ◽  
Langmuir Kinetics

The rate constants and equilibrium constant for the adsorption and desorption of lipid vesicles from a SiO2 surface have been determined.

A cell-penetrating peptide induces the self-reproduction of phospholipid vesicles: understanding the role of the bilayer rigidity

2018 ◽  
Vol 54 (81) ◽  
pp. 11451-11454 ◽  
Author(s):  
Pavel Banerjee ◽  
Siddhartha Pal ◽  
Niloy Kundu ◽  
Dipankar Mondal ◽  
Nilmoni Sarkar
Keyword(s):  
Lipid Vesicles ◽  
The Self ◽  
Phospholipid Vesicles ◽  
Cell Penetrating Peptide ◽  
Cell Penetrating ◽  
A Cell

Model lipid vesicles (LAPC) self-reproduce to generate unilamellar daughter vesicles in the presence of a cell-penetrating peptide (R9) due to a loss of the bilayer rigidity.

Association of the nucleocapsid protein N of vesicular stomatitis virus with phospholipids vesicles containing the matrix protein M

1984 ◽  
Vol 62 (11) ◽  
pp. 1174-1180 ◽  
Author(s):  
John Capone ◽  
Hara P. Ghosh
Keyword(s):  
Vesicular Stomatitis Virus ◽  
Nucleocapsid Protein ◽  
Matrix Protein ◽  
Lipid Vesicles ◽  
Viral Envelope ◽  
M Protein ◽  
Phospholipid Vesicles ◽  
N Protein ◽  
The Matrix ◽  
Vesicular Stomatitis

The matrix protein M and the nucleocapsid protein N were isolated from vesicular stomatitis virus and reconstituted into artificial phospholipid vesicles. While the M protein could be reconstituted into phospholipid vesicles, the N protein had no affinity for lipid vesicles. The N protein could, however, associate with phospholipid vesicles in the presence of M protein. Identical results were also obtained when an in vitro system synthesizing M and N proteins was used for reconstitution. The results suggest that M protein is involved in virus maturation by interacting with the viral envelope and the N protein of the nucleoprotein core.

scholarly journals Circular-dichroism and fluorescence studies on melittin: effects of C-terminal modifications on tetramer formation and binding to phospholipid vesicles

1995 ◽  
Vol 305 (3) ◽  
pp. 785-790 ◽  
Author(s):  
M van Veen ◽  
G N Georgiou ◽  
A F Drake ◽  
R J Cherry
Keyword(s):  
Fluorescence Probe ◽  
Alpha Helix ◽  
Lipid Vesicles ◽  
Lipid Binding ◽  
Phospholipid Vesicles ◽  
Tryptophan Residue ◽  
Fluorescence Studies ◽  
Helix Formation ◽  
Tetramer Formation ◽  
Self Association

Studies were performed on a series of melittin analogues with selective alterations to the positively charged amino acid sequence at the C-terminus. Fluorescence studies were undertaken using the sole tryptophan residue in the analogues as an intrinsic fluorescence probe for indications of tetramer formation in free solution, and binding and insertion of the melittins into phospholipid bilayers. Studies were performed under conditions of low-salt buffer with increasing concentrations of phosphate added to promote self-association of the melittin monomers, and also in the presence of phospholipid vesicles. C.d. studies were also performed under conditions of increasing phosphate concentrations and in the presence of lipid vesicles to monitor the alpha-helical content of the melittins. It was found that selective replacement of the C-terminal basic amino acids by glutamine has different effects on self-association, alpha-helix formation and lipid binding of melittin.

Comparison on Regulation of Calcium Phosphate by Organic Monolayer, Unilamellar Phospholipid Vesicles and Hydrothermal Self-Assembly

1999 ◽  
Vol 599 ◽  
Author(s):  
F. Z. Cui ◽  
Y. Zhang ◽  
Q. Cai
Keyword(s):  
Calcium Phosphate ◽  
Thin Layer ◽  
Self Assembly ◽  
Sol Gel ◽  
Lipid Vesicles ◽  
Phospholipid Vesicles ◽  
Monolayer Films ◽  
Organic Monolayer ◽  
Self Organized ◽  
Nucleation Growth

AbstractBiomineralization centers on the idea that organics control the nucleation, growth and final form of inorganics. The present studies investigated the deposition or precipitation of inorganics templated by organic monolayer films, unilamellar phospholipid vesicles, and selfassembled hexadecylamine, with the emphasis on the regulation of template on phase, orientation and microstructure of minerals. The obtained calcium phosphate varied from the thin layer precipitated on the organic monolayer to the confined particles formed inside the lipid vesicles to the mesolamellar structure self-organized in the precursor sol-gel. The typically regulated features of these three systems have been revealed. Consequently, the different phases of calcium phosphate can be obtained through variation of controllable parameters.

scholarly journals Induction of tyrosine aminotransferase in H-35 hepatoma cells by cAMP captured in phospholipid vesicles.

1981 ◽  
Vol 88 (1) ◽  
pp. 89-95 ◽  
Author(s):  
J A Culpepper ◽  
A Y Liu
Keyword(s):  
Cyclic Nucleotide ◽  
Lipid Vesicles ◽  
Tyrosine Aminotransferase ◽  
Hepatoma Cells ◽  
Receptor Protein ◽  
Regulatory Subunit ◽  
Phospholipid Vesicles ◽  
Intracellular Camp ◽  
Intact Cells ◽  
Relationship Of

The uptake, metabolism, and action of cAMP, captured within phospholipid vesicles, in H-35 hepatoma cells were studied. Sonication of lipids in buffer containing cAMP resulted in the formation of 300-A unilamellar lipid vesicles, capturing cAMP in the internal aqueous cavity. Incubation of H-35 hepatoma cells with vesicles containing cAMP (vesicle-cAMP) resulted in rapid incorporation of the vesicle content; apparent saturation of uptake was reached after approximately 30 min of incubation at 37 degrees C. Uptake of vesicle-cAMP was linear over a 10-fold vesicle concentration range. Pretreatment of cells with combined inhibitors of glycolysis and respiration inhibited vesicle uptake by 27%, suggesting vesicle fusion with the cell membrane as a predominant pathway of vesicle uptake. Studies on the metabolism of incorporated cAMP indicated that greater than 50% of the cell-associated radioactivity, derived from vesicle-[3H]cAMP, was preserved as cAMP at the end of a 20-min incubation at 37 degrees C. The incorporation of vesicle-cAMP by H-35 hepatoma cells resulted in increased tyrosine aminotransferase (TAT) activity. The concentration of vesicle-cAMP needed to produce a half-maximal increase in TAT activity was 10 microM, approximately two orders of magnitude lower than that of exogenously added dbcAMP. cAMP was ineffective when added extracellularly. The kinetic relationship of the cAMP-induced increase in TAT activity and the binding of cAMP to its receptor protein, in intact H-35 cells, was examined using vesicle-trapped 8-N3-cAMP, a photoaffinity labeling analogue of cAMP. Incubation of H-35 hepatoma cells with vesicle-8-N3-cAMP resulted in increased TAT activity, preceded by the binding of 8-N3-cAMP to the regulatory subunit of type II cAMP-dependent protein kinase. The use of lipid vesicles provides a means of modulating intracellular cAMP concentration without adding cyclic nucleotide in the millimolar concentration range to the extracellular medium. The increased efficiency of intracellular delivery of cyclic nucleotide with retention of biological activity, provides a useful technique in examining the relationship of occupancy of specific cAMP-receptor protein(s) and the occurrence of a cAMP-mediated biological response in intact cells.

On the existence of an amphotericin B – sterol complex in lipid vesicles and in propanol–water systems

1987 ◽  
Vol 65 (3) ◽  
pp. 234-238 ◽  
Author(s):  
Ilona Gruda ◽  
Jacques Bolard
Keyword(s):  
Circular Dichroism ◽  
Amphotericin B ◽  
Lipid Bilayer ◽  
Binary Mixtures ◽  
Lipid Vesicles ◽  
Water Systems ◽  
Phospholipid Vesicles ◽  
Positive Cooperativity ◽  
Circular Dichroïsm

The amphotericin B (AmB) – ergosterol complex, formed by interaction of the antibiotic with ergosterol-containing phospholipid vesicles, is associated with the lipid bilayer. It has been shown by circular dichroism studies that the AmB–ergosterol complex formed in water–propanol binary mixtures has a similar structure to that observed in phospholipid vesicles. A positive cooperativity is found for the interaction of AmB with ergosterol. The similar AmB–cholesterol complex is much less stable and rearranges rapidly to a different conformation.

scholarly journals Synthetic phospholipid vesicles containing a purified viral antigen and cell membrane proteins stimulate the development of cytotoxic T lymphocytes.

1979 ◽  
Vol 150 (5) ◽  
pp. 1067-1074 ◽  
Author(s):  
D Loh ◽  
A H Ross ◽  
A H Hale ◽  
D Baltimore ◽  
H N Eisen
Keyword(s):  
T Lymphocytes ◽  
Membrane Proteins ◽  
Cell Membrane ◽  
G Protein ◽  
Cytotoxic T Lymphocytes ◽  
Effective Interaction ◽  
Lipid Vesicles ◽  
Phospholipid Vesicles ◽  
Target Cells ◽  
Cell Membrane Proteins

Synthetic phospholipid vesicles (liposomes) containing the purified glycoprotein (G) of vesicular stomatitis virus (VSV) and solubilized membrane proteins from cells of the appropriate H-2 haplotype elicited H-2-restricted cytotoxic T lymphocytes (CTL) that lysed VSV-infected target cells. The CTL were elicited by intact liposomes, not by released components. Thus, when spleen cells from VSV-primed H-2d X H-2b hybrid mice were stimulated with liposomes having G protein + membrane proteins from cells with one of the parental H-2 haplotypes, the resulting CTL lysed only VSV-infected target cells with that parent's H-2 type. This result argues against the view that T cells in general recognize only processed antigenic fragments on macrophages. Moreover, liposomes were only effective when G protein and cell membrane proteins were included in the same vesicles. This result suggests that for effective interaction with CTL precursors the antigen (G protein) and products of the H-2 complex must be closer to each other than 600--1,000 angstrom, the diameter of the lipid vesicles used in this study.

Functional incorporation and preferred orientation of phytohemagglutinin receptor glycoproteins in phospholipid vesicles

1987 ◽  
Vol 65 (2) ◽  
pp. 120-129 ◽  
Author(s):  
Gilles Dupuis ◽  
Marc Letellier
Keyword(s):  
Cultured Cells ◽  
Lymphocyte Activation ◽  
Lipid Vesicles ◽  
Simultaneous Action ◽  
Phospholipid Vesicles ◽  
Lectin Receptor ◽  
Low Concentrations ◽  
Binding Data ◽  
Combined Action ◽  
Tritium Labeling

Porcine lymphocyte Phaseolus vulgaris phytohemagglutinin (PHA) receptor glycoproteins purified by affinity chromatography have been reassembled into vesicles made of phosphatidylcholine and phosphatidylserine by detergent (dodecyltrimethylammonium bromide) dialysis. The receptor glycoproteins were incorporated into the lipid vesicles in a nonselective manner with a yield of 65–70%. Vesicles containing the glycoproteins were sealed as evidenced by their impermeability to calcium ions, using quin 2 trapped inside the vesicles. The vesicles were agglutinated by PHA, suggesting that the saccharidic moiety of the reconstituted glycoproteins was, at least in part, oriented towads the extravesicular medium. This observation was further supported by the fact that the vesicles bound 125I-labeled PHA in a specific and saturable manner. At maximum amount of lectin bound, a ratio of 1.01 ± 0.05 μg of PHA per microgram glycoprotein incorporated was measured. When the binding data were analyzed by Scatchard plot, a downward concave profile was observed, suggestive of a positive cooperativity at low concentrations of lectin. The orientation of the reconstituted lectin receptor glycoproteins was determined by proteolytic treatments of labeled glycoproteins. The combined action of trypsin and chymotrypsin released, in the 120 000 × g supernatant, approximately 80% of label when 125I-tagged PHA receptor glycoproteins were incorporated into the vesicles. When the oligosaccharidic moieties of the receptor glycoproteins were specifically labeled, the simultaneous action of the two enzymes released approximately 70% of tritium labeling present in the reconstituted system. Taken together, these results suggest that the reconstituted PHA receptors are preferentially oriented into the phospholipid vesicles. The reconstituted PHA receptor glycoproteins competed effectively with cellular receptors in the assay of PHA-induced porcine lymphocyte activation. A 50% inhibition of [3H]thymidine incorporation was observed when 1 μg of glycoproteins in vesicles was added to the cultured cells, whereas vesicles alone had no effect at this (equivalent) concentration.

Sign in / Sign up

Export Citation Format

Share Document