Biological membrane lipid bilayer (Lipid bilayer)

The biological membrane lipid bilayer is a fundamental structural component of all living cells, consisting of two layers of amphipathic phospholipids arranged tail-to-tail (Alberts et al., 2014). It serves as a semi-permeable barrier that separates the internal cellular environment from the external surroundings, facilitating compartmentalization and maintaining ion gradients essential for life (Van Meer et al., 2008). Beyond its structural role, the lipid bilayer acts as a dynamic platform for signal transduction, protein anchoring, and membrane trafficking (Simons & Gerl, 2010). In pharmacology, the lipid bilayer is a critical therapeutic target, particularly for antimicrobial and antifungal agents that exploit differences in lipid composition between pathogens and host cells (Zasloff, 2002). For instance, drugs like daptomycin and polymyxins disrupt bacterial membrane integrity, while polyene antifungals like amphotericin B target sterols within the bilayer to induce pore formation (Baginski & Tugnoli, 2012). General anesthetics are also thought to interact with the lipid bilayer, potentially altering its physical properties to influence the function of embedded membrane proteins (Sonnleitner et al., 2002). However, targeting the lipid bilayer presents significant safety challenges due to the potential for cross-reactivity with human cell membranes, often leading to dose-limiting toxicities such as nephrotoxicity (Velkov et al., 2013). Research into membrane-active agents continues to focus on increasing selectivity for specific lipid species, such as phosphatidylglycerol in bacteria or ergosterol in fungi, to minimize host damage (Mouritsen, 2011).

Other names

Cell membranePlasma membranePhospholipid bilayerCytoplasmic membrane

Membrane permeabilization, pore formation, depolarization, and disruption of lipid packing (Zasloff, 2002; Baginski & Tugnoli, 2012).