Fabricating a New Stabilized Lipid-Based Platform for Handling and Presenting GPCRs

Abstract

In model lipid bilayers, ethanol is known to alter the mechanical and thermodynamic properties of the membrane. The extent to which alcohol affects these properties depends upon the lipid composition of the bilayer. Our group has demonstrated that increased ergosterol levels in model membrane systems mitigate the membrane thinning effect of ethanol -a phenomenon known as interdigitation. Perturbations to the yeast biomembrane due to increasing ethanol levels has been implicated in reduced sugar utilization and cell viability in Saccharomyces sp. However, variations in fermentation conditions and analytical methods have not yielded a comprehensive picture of how yeast biomembranes adapt to increasing levels of ethanol. In this work, we analyzed the partial lipidome of 30 industrial yeast strains at different stages of fermentation using high-resolution mass spectrometry. Quantification of selected lipid species was performed using high performance liquid chromatography coupled online to quadrupole ion-trap mass spectroscopy. Multivariate statistical analysis of the quantitative data was performed to determine any correlations between changes in lipid composition and ethanol tolerance in the different yeast strains. Information regarding how yeast biomembranes adapt to greater ethanol concentrations will be used to construct biophysical models to analyze the complex physical properties of lipid biomembranes in an alcohol milieu.