Location and effect of ergosterol inside membranes

摘要: Sterols are an important class of lipids that regulate many biological processes. Among them, cholesterol from animal cell membranes, has been studied extensively, while ergosterol in fungi and some protists is surprisingly understudied. Based on their similarity in chemical structure, ergosterol is assumed to maintain the membrane fluidity and stability with the comparable biophysical and biochemical properties as cholesterol. However, recent studies start to indicate disparities in their effects on membranes. Since ergosterol is indispensable in fungi cells and is targeted by antimicrobial drugs such as amphotericin B, it is imperative to have more fundamental understandings of its effect on membranes. In this study, we pinpoint the location of ergosterol inside a model membrane (POPC) with neutron membrane diffraction (NMD). It is embedded much shallower in the bilayer than cholesterol. From both NMD and …