Engineering cell membranes–the effect of pH on the formation, structure, and mobility of biomimetic cell membranes
[ 1 ] Instytut Fizyki, Wydział Inżynierii Materiałowej i Fizyki Technicznej, Politechnika Poznańska | [ S ] student | [ P ] employee | [ SzD ] doctoral school student
2022
scientific article / paper
english
EN The lateral segregation and compartmentalization of lipids within cell membranes are strongly related to many biological processes occurring in the body such as protein sorting, ion-channel regulation, signalling, organization of the cytoskeleton, and pathogen entry. Moreover, lipid domains composed of ordered phase are associated with the binding of toxins and their penetration inside the cell. The importance of the lipid domain formation and activity triggered studies on the active manipulation of their structural properties. Here, we present systematic study on the formation,dynamics, and stability of the phase-separated, supported lipid bilayers (SLBs) under varying pH conditions. The used composition of phosphatidylcholine (14:1 PC), cholesterol and sphingomyelin (SM) leads to the formation of liquid-ordered (Lo) and liquid-disordered (Ld) phases. The effect of pH on the formation, structure and dynamics of biomimetic membranes was investigated in a wide range of pH values: 1.7–9.0, with the use of fluorescence confocal microscopy and fluorescence recovery after photobleaching (FRAP) techniques, respectively. We discovered that lipid domain size is very sensitive to the pH conditions and increases significantly with increasing pH this allows for modulating and inducing the formation of Lo domains of a specific size solely by varying pH of the environment, without any external modification of the solid support or altering of membrane composition. Interestingly, the diffusion coefficient of lipids in both Lo and Ld phase remains unaltered at different pH conditions. Our studies demonstrate the possibility of active manipulation of the lateral organization of lipid membranes and enables further studies focused on mutual interactions between proteins and other molecules binding specifically to lipid domains in membranes subjected to varying pH conditions.
07.07.2022
269 - 270
CC BY (attribution alone)
open journal
final author's version
at the time of publication
70
2,6