Membrane fusion mediated by peptidic SNARE protein analogues: Evaluation of FRET‐based bulk leaflet mixing assays

Abstract

Peptide‐mediated membrane fusion is frequently studied with in vitro bulk leaflet mixing assays based on Förster resonance energy transfer (FRET). In these, customized liposomes with fusogenic peptides are equipped with lipids which are labeled with fluorophores that form a FRET pair. Since FRET is dependent on distance and membrane fusion comes along with lipid mixing, the assays allow for conclusions on the membrane fusion process. The experimental outcome of these assays, however, greatly depends on the applied parameters. In the present study, the influence of the peptides, the size of liposomes, their lipid composition and the liposome stoichiometry on the fusogenicity of liposomes are evaluated. As fusogenic peptides, soluble N‐ethylmaleimide‐sensitive‐factor attachment receptor (SNARE) protein analogues featuring artificial recognition units attached to the native SNARE transmembrane domains are used. The work shows that it is important to control these parameters in order to be able to properly investigate the fusion process and to prevent undesired effects of aggregation.

Study on Artificial Light‐Harvesting System Based on Polymer Organogels

“…In other words, when the emission spectrum of one fluorescent molecule overlaps with the absorption spectrum of another fluorophore and the distance between the two fluorophores is appropriate, the phenomenon of FRET from the donor to the receptor can be observed. Thus far, considerable progress has been made in simulating natural light harvesting by transferring energy from a donor to a receptor through FRET [12–15] . For example, Guo et al.…”

“…Thus far, considerable progress has been made in simulating natural light harvesting by transferring energy from a donor to a receptor through FRET. [12][13][14][15] For example, Guo et al reported WP6-G-NiR and WP6-G-ESY systems, which exhibited high antenna effects (AEs). [16] Notably, most studies on ALHSs have employed organic solutions; however, owing to the stability of polymer gels, ALHSs show greater promise in polymer gel materials.…”