Bacterial lipid membrane

The bacterial lipid membrane is a fundamental structural component of all bacteria, serving as a semi-permeable barrier that separates the cytoplasm from the external environment. It consists primarily of a phospholipid bilayer interspersed with proteins that facilitate essential processes such as nutrient transport, energy transduction via the electron transport chain, and signal transduction (Sohlenkamp & Geiger, 2016, Bacterial membrane lipids: diversity in structures and pathways, FEMS Microbiology Reviews). In Gram-positive bacteria, the membrane is surrounded by a thick peptidoglycan layer, while Gram-negative bacteria possess both an inner cytoplasmic membrane and an outer membrane containing lipopolysaccharides (Epand et al., 2016, Bacterial membrane lipids in the action of antimicrobial agents, Journal of Peptide Science). This structure is a critical therapeutic target because its disruption leads to the leakage of intracellular contents, loss of membrane potential, and rapid cell death. Drugs like daptomycin target the membrane of Gram-positive bacteria by inserting into the bilayer in a calcium-dependent manner, causing depolarization (Heidary et al., 2017, Daptomycin, Drug Design, Development and Therapy). Conversely, polymyxins target the outer and inner membranes of Gram-negative bacteria by interacting with negatively charged lipids, making them last-resort treatments for multi-drug resistant infections (Poirel et al., 2017, Polymyxins: Antibacterial Activity, Susceptibility Testing, and Resistance Mechanisms, Clinical Microbiology Reviews).

Other names

Bacterial cytoplasmic membraneBacterial plasma membraneBacterial cell membraneBacterial inner membrane

Membrane depolarization, pore formation, disruption of membrane integrity, and inhibition of lipid-linked cell wall precursors.