Bacterial and fungal cell membrane lipid bilayer

The bacterial and fungal cell membrane lipid bilayer is a vital semi-permeable barrier that separates the internal cytoplasm from the external environment, maintaining the electrochemical gradients necessary for ATP synthesis and nutrient transport (Source: Molecular Biology of the Cell, 6th ed.). In bacteria, the membrane is rich in anionic phospholipids like phosphatidylglycerol, which serves as a docking site for lipopeptide antibiotics like daptomycin (Source: StatPearls, Daptomycin). Fungal membranes are distinguished by the presence of ergosterol, a sterol that maintains membrane fluidity and is absent in mammalian cells, which use cholesterol instead (Source: Journal of Fungi, 2021). This biochemical difference is exploited by polyene antifungals like Amphotericin B, which bind ergosterol to form lethal transmembrane pores (Source: NIH, PubChem). Drugs targeting the lipid bilayer are often bactericidal or fungicidal because they cause rapid loss of cytoplasmic contents, such as potassium ions, leading to immediate metabolic arrest (Source: Nature Reviews Microbiology, 2017). However, the structural similarity between microbial and host membranes can lead to significant clinical toxicities, particularly nephrotoxicity seen with polymyxins and polyenes (Source: Clinical Infectious Diseases, 2019).

Other names

Microbial cell membraneCytoplasmic membranePlasma membraneBacterial inner membraneFungal plasma membrane

Disruption of membrane integrity through pore formation, depolarization, or binding to specific lipid components (e.g., ergosterol or phosphatidylglycerol), leading to leakage of essential intracellular ions and cell death.