Bacterial cell membrane phospholipid and lipopolysaccharide

Bacterial cell membrane phospholipids form the fundamental structure of all bacterial cytoplasmic membranes, comprising a bilayer of amphipathic molecules with hydrophilic head groups facing outward and hydrophobic tails inward[1][3][5]. These provide membrane integrity, selective permeability, and act as dynamic sites for protein binding, cellular signaling, and environmental interaction[1][5][9]. In Gram-negative bacteria, the outer membrane contains lipopolysaccharide (LPS), a large glycolipid composed of lipid A (a hydrophobic anchor in the membrane), core oligosaccharide, and O-antigen[4][6][10]. The lipid A moiety is primarily responsible for the strong immunostimulatory properties of LPS, which can trigger severe inflammatory responses in animals and humans[4][6]. LPS also confers resistance to some antibiotics and protects bacteria against hostile environments[7][10]. Drugs such as polymyxins exploit the negative charge and hydrophobicity of these bacterial membrane lipids, disrupting membrane integrity to induce cell death; however, these drugs can be toxic to host tissues and bacterial resistance is increasingly reported. The high structural variability of LPS enables immune evasion and forms the basis for bacterial strain serotyping[2][8][10].

Other names

Phospholipid bilayer (for bacterial membrane)LPS (lipopolysaccharide)bacterial lipid bilayerlipid A (specific ligand in LPS)Gram-negative bacterial outer membrane components

Disruption of membrane integrity (pore formation, destabilization: polymyxins, antimicrobial peptides); Binding and neutralization of LPS (LPS antagonists, e.g. eritoran); Inhibition or enhancement of immune recognition (by modulating LPS structure)