Cellular membrane phospholipids and associated membrane proteins

The cellular membrane is a dynamic and complex assembly consisting of a phospholipid bilayer interspersed with cholesterol and various integral and peripheral membrane proteins. Phospholipids, such as phosphatidylcholine and phosphatidylserine, provide the structural matrix that maintains cellular integrity and regulates the movement of substances via semi-permeability (Alberts et al., Molecular Biology of the Cell). Associated membrane proteins, including G protein-coupled receptors and ion channels, are essential for signal transduction and maintaining electrochemical gradients. In therapeutic contexts, this assembly is targeted by specialized antibiotics like polymyxins, which bind to bacterial lipopolysaccharides and phospholipids to disrupt membrane stability, and antifungal agents like amphotericin B that target membrane sterols (Velkov et al., 2013, Journal of Medicinal Chemistry). Pathological changes in membrane composition or protein association are implicated in diseases ranging from cancer, where membrane fluidity affects metastasis, to antiphospholipid syndrome, an autoimmune condition characterized by antibodies against membrane components (Miyakis et al., 2006, Journal of Thrombosis and Haemostasis). Because these structures are ubiquitous, pharmacological intervention requires high specificity to distinguish between the membranes of pathogens and those of the human host to avoid significant off-target toxicity.

Other names

Plasma membrane componentsLipid bilayer and membrane-bound proteinsCell membrane matrixBiological membrane

Drugs targeting this complex typically act through membrane disruption, pore formation, alteration of membrane fluidity, or competitive inhibition of membrane-bound receptors and transporters (Humphries et al., 2013, Clinical Microbiology Reviews). For example, lipopeptides insert into the lipid bilayer to cause rapid depolarization, while polyenes bind to sterols to induce lethal ion leakage (Gray et al., 2014, PNAS).