Abstract
Lipid vesicles, in particular Giant Unilamellar Vesicles (GUVs), have been increasingly important as compartments of artificial cells to reconstruct living cell-like systems in a bottom-up fashion. Here, we report shape transformations of lipid vesicles induced by polyethylene glycol-lipid conjugate (PEG lipids). Statistical analysis of deformed vesicle shapes revealed that shapes vesicles tend to deform into depended on the concentration of the PEG lipids. When compared with theoretically simulated vesicle shapes, those shapes were found to be more energetically favorable, with lower membrane bending energies than other shapes. This result suggests that the vesicle shape transformations can be controlled by externally added membrane molecules, which can serve as a potential method to control the replications of artificial cells.
Highlights
Lipid vesicles, in particular Giant Unilamellar Vesicles (GUVs) have long been employed as model cell membranes to elucidate the physicochemical basis of biological cellular functions
If not all, vesicles showed similar transformations regardless of the micelle concentrations. This series of shape transformations were observed in both cases when fluorescent polyethylene glycol (PEG) lipid micelles (DSPE-PEG(2000) CF) and biotinylated PEG lipid micelles (DSPE-PEG(2000) Biotin) were added
In the case of biotinylated PEG lipids, a larger portion of vesicles exhibited division into two or more daughter vesicles at the higher micelle concentrations tested and the transformations appeared to have completed within 15 min after the addition of PEG lipid
Summary
In particular Giant Unilamellar Vesicles (GUVs) have long been employed as model cell membranes to elucidate the physicochemical basis of biological cellular functions. While even simplest bacterial cells are still complex, lipid vesicles are simple enough and amenable to alteration of membrane compositions and inner aqueous contents. They have been used in biophysical studies investigating, for example, lipid raft formation, [1, 2] interaction with small molecules and peptides, [3, 4] and morphological transformations upon external stimulations. [5, 6] In recent years, lipid vesicles are increasingly used as compartments of artificial cells, or “protocells”, to reconstruct living cell-like systems in a bottom-up fashion. Protein expression, [7, 8] cascade reaction, [9] RNA self-replication, [10] directed evolution of an enzyme [11] and membrane protein, [12, 13] programmed vesicle fusion [14, 15] and reconstruction of membrane protein complex [16] have been demonstrated.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
