Bacterial and fungal cell membrane phospholipid bilayers

The bacterial and fungal cell membrane phospholipid bilayers are essential structural components that maintain the integrity and internal environment of microbial cells. In bacteria, the cytoplasmic membrane is a site for critical metabolic processes, including ATP synthesis via the electron transport chain and the transport of nutrients and waste (NCBI: Bacterial Cell Chemistry). Fungal membranes are characterized by the presence of ergosterol, a sterol unique to fungi that regulates membrane fluidity and permeability, serving as a primary distinction from mammalian cholesterol-rich membranes (StatPearls: Amphotericin B). These membranes serve as vital therapeutic targets; drugs such as polymyxins and daptomycin disrupt bacterial membranes through electrostatic interactions with negatively charged lipids or calcium-dependent insertion (PubMed: Daptomycin Mechanism). Polyene antifungals like amphotericin B bind directly to ergosterol to create lethal pores in the fungal bilayer. Disruption of the bilayer leads to rapid depolarization, leakage of intracellular ions like potassium, and subsequent cell death, making these targets effective against a wide range of pathogens, including those resistant to traditional cell wall synthesis inhibitors (StatPearls: Polymyxins).

Other names

Microbial cell membraneCytoplasmic membranePlasma membranePhospholipid bilayerBacterial inner membrane

Disruption of membrane integrity, pore formation, and depolarization leading to loss of membrane potential and leakage of cytoplasmic contents.