Fungal plasma membrane ergosterol-containing lipid bilayer

The fungal plasma membrane ergosterol-containing lipid bilayer is a fundamental structural component of fungal cells, where ergosterol serves as the primary sterol, analogous to cholesterol in mammalian cells (Luo et al., 2021, 'Ergosterol: A Review'). It plays a critical role in maintaining membrane fluidity, integrity, and the proper functioning of membrane-associated proteins and transport systems (Wikipedia, 'Ergosterol'). This lipid bilayer is a primary target for polyene antifungal agents, such as amphotericin B and nystatin, which bind specifically to ergosterol (StatPearls, 'Amphotericin B'). The interaction between these drugs and the ergosterol-rich bilayer leads to the formation of aqueous pores or the sequestration of ergosterol into 'sponges,' resulting in the leakage of essential intracellular components like potassium ions and ultimately causing cell death (Gray et al., 2012, 'Amphotericin B causes cell death by sequestering ergosterol'). Because ergosterol is absent in human cell membranes, this bilayer provides a basis for selective toxicity, although high doses can lead to side effects due to structural similarities between ergosterol and human cholesterol (NIH, 'Antifungal Agents').

Other names

ErgosterolFungal cell membraneErgosterol-rich lipid bilayerErgosta-5,7,22-trien-3β-ol

Direct binding to ergosterol molecules within the fungal plasma membrane, leading to the formation of transmembrane pores or the sequestration of sterols into large aggregates, which causes rapid leakage of intracellular ions (e.g., K+) and small molecules, resulting in fungal cell death.