Biomimetic vesicle

Katz M, Tsubery H, Kolusheva S, Shames A, Fridkin M, Jelinek R. Lipid binding and membrane penetration of polymyxin B derivatives studied in a biomimetic vesicle system. Biochem J 2003 375 405-413. 

Sheynis T, Sykora J, Benda A, Kolusheva S, Hof M, Jelinek R. Bilayer localization of membrane-active peptides studied in biomimetic vesicles by visible and fluorescence spectroscopies. Eur J Biochem 2003 270 4478-4487. 

The interaction of the homopolymers of this series with biomimetic vesicles was examined by Gabriel et to understand the mechanism of antimicrobial activity and selectivity. Dye leakage of quenched calcein-filled vesicles was measured upon exposure to polymers of series C19. The vesicles consisted of 3 1 POPE POPG lipids to mimic the composition of E. coli membranes. Across the series, dye leakage correlated with... 

In summary, these recently obtained results demonstrate that certain amphi-pathic peptoid sequences designed to mimic both the helical structure and approximate length of magainin helices are also capable of selective and biomimetic antibacterial activity. These antibacterial peptoids are helical in both aqueous buffer and in the presence of lipid vesicles. Ineffective (non-antibacterial) peptoids exhibit weak, random coil-like CD, with no spectral intensification in the presence of lipid vesicles. Selective peptoids exhibit stronger CD signals in bacterial-mimetic vesicles than in mammalian-mimetic vesicles. Non-selective peptoids exhibit intensely helical CD in both types of vesicles. 

Much of the impetus for the study of reactions in micelles is that they model, to a limited extent, reactions in biological assemblies. Synthetic vesicles and cyclodextrins are other model reaction media and the term Biomimetic Chemistry has been coined to describe this general area of study. Work in this area is reviewed in recent publications (Kunitake and Shinkai, 1980 Fendler, 1982). 

Halevy R, Rozek A, Kolusheva S, Hancock RE, Jelinek R. Membrane binding and permeation by indolicidin analogs studied by a biomimetic lipid/polydiacetylene vesicle assay. Peptides 2003 24 1753-1761. 

Directed self-assembly processes are those which involve a template, whether or not it ends up in the final structure. Typical examples are vesicle-directed biomimetic mineralisation strategies (Section 15.3)... 

Roks, M. F. M. Nolte, R. J. M., (1992) Biomimetic macromolecular chemistry design and synthesis of an artificial ion channel based on a polymer containing cofacially stacked crown ether rings. Incorporation in dihexadecyl phosphate vesicles and study of cobalt ion transport Macromolecules 25, 5398-5407. 

Vesicles have demonstrated their dynamic behaviour in studies showing evidence of rapid domain formation in response to external stimuli [9], The binding of glycosidic domains to cholera toxin has been demonstrated using vesicles as biomimetic sensors [99], Protein-carbohydrate interaction has also been studied using synthetic glycolipids recently by Barboiu et al. [100] (Fig. 5). 

As an intermediate between solid supported layers and the inherent dynamic and nanostructured properties of phospholipid vesicle supports, silica and especially mesoporous silica nanoparticles may provide interesting platforms for dynamic bilayers. Previous studies have shown that stable bilayers can form on both amorphous [102] or functional silica [103, 104] and mesoporous nanoparticles [105] or membranes [106]. This type of biomimetic carrier has great potential as a type of trackable stabilized membrane capable of displaying cellular targeting elements in a close to natural configuration. 

Methodologies for the fabrication of biomimetic membranes vary somewhat from one biomimetic membrane to another. However, a number of experimental procedures for the formation of lipid monolayers and bilayers on solid supports are common to several biomimetic membranes. The most popular procedures are vesicle fusion, Langmuir-Blodgett and Langmuir-Schaefer transfers, and rapid solvent exchange. The formation of lipid monolayers and bilayers on gold and... 

Yang, P., Lipowsky, R., and Dimova, R. (2009) Nanoparficle formation in giant vesicles synthesis in biomimetic compartments. Small, 5 (18), 2033-2037. 

Abstract The aggregation behaviour of biomimetic polypeptide hybrid copolymers and copolypeptides is here reviewed with a particular eye on the occurrence of secondary structure effects. Structure elements like a-helix or / -sheet can induce a deviation from the classical phase behaviour and promote the formation of vesicles or hierarchical superstructures with ordering in the length-scale of microns. Polypeptide copolymers are therefore considered as models to study self-assembly processes in biological systems. In addition, they offer a great potential for a production of novel advanced materials and colloids. 

The phase behaviour of biomimetic polypeptide-based copolymers in solution was described and discussed with respect to the occurrence of secondary structure effects. Evidently, incorporation of crystallisable polypeptide segments inside the core of an aggregate has impact on the curvature of the corecorona interface and promotes the formation of fibrils or vesicles or other flat superstructures. Spherical micelles are usually not observed. Copolymers with soluble polypeptide segments, on the other hand, seem to behave like conventional block copolymers. A pH-induced change of the conformation of coronal polypeptide chains only affects the size of aggregates but not their shape. The lyotropic phases of polypeptide copolymers indicate the existence of hierarchical superstructures with ordering in the length-scale of microns. 

Simao AM, Yadav MC, Narisawa S et al (2010) Proteoliposomes harboring alkaline phosphatase and nucleotide pyrophosphatase as matrix vesicle biomimetics. J Biol Chem 285 7598-7609... 

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