Bacterial cell membrane and cell envelope

The bacterial cell envelope is a complex multi-layered structure that serves as the primary interface between a bacterium and its environment (Silhavy et al., 2010, Nature Reviews Microbiology). It typically comprises the inner cytoplasmic membrane and a surrounding cell wall; in Gram-positive organisms, this is characterized by a thick layer of peptidoglycan, while Gram-negative organisms possess a thinner peptidoglycan layer and an additional outer membrane rich in lipopolysaccharides (Sperandeo et al., 2017, FEBS Letters). This structure is essential for maintaining cellular integrity, protecting against osmotic lysis, and regulating the transport of nutrients and waste (StatPearls, 2023). Because the cell envelope contains components unique to bacteria, such as peptidoglycan, it is a premier target for many classes of antibiotics (Kohanski et al., 2010, Nature Reviews Microbiology). Drugs like beta-lactams and glycopeptides interfere with the synthesis and cross-linking of the cell wall, leading to bacterial lysis, while others like polymyxins and lipopeptides directly disrupt the physical integrity of the membranes (Cui et al., 2023, Frontiers in Microbiology). Understanding the envelope's composition is critical for developing treatments against increasingly resistant bacterial pathogens.

Other names

Bacterial cell wallBacterial envelopeCytoplasmic membraneOuter membranePeptidoglycan layer

Inhibition of peptidoglycan synthesis and cross-linking (beta-lactams, glycopeptides), disruption of cytoplasmic membrane integrity and potential (lipopeptides), and competitive displacement of divalent cations in the outer membrane (polymyxins) (StatPearls, 2023; Kohanski et al., 2010, Nature Reviews Microbiology).