Bacterial cell envelope and membrane

The bacterial cell envelope is a complex, multi-layered structure that serves as the primary interface between a bacterium and its environment, providing structural integrity and protection against osmotic pressure. It typically comprises the inner cytoplasmic membrane and a peptidoglycan-based cell wall, with Gram-negative bacteria possessing an additional outer membrane containing lipopolysaccharides (Silhavy et al., 2010). This structure is a fundamental therapeutic target because many of its components, such as peptidoglycan, are unique to bacteria, allowing for high selective toxicity (Kohanski et al., 2010). Antibiotics like beta-lactams and glycopeptides target the synthesis of the cell wall, while polymyxins and lipopeptides directly disrupt the integrity of the lipid membranes (Zheng et al., 2017). Beyond its role as a target, the envelope acts as a formidable barrier to drug penetration, and its modification is a central mechanism in the development of antibiotic resistance (Delcour, 2009). Consequently, understanding the envelope's composition is critical for the design of novel antimicrobial agents capable of overcoming protective barriers.

Other names

Bacterial cell wallCytoplasmic membraneOuter membranePeptidoglycan layerCell envelope

Inhibition of peptidoglycan biosynthesis through the targeting of transpeptidases and transglycosylases, disruption of cytoplasmic membrane potential and permeability, and binding to lipopolysaccharides or lipid II to compromise the structural integrity of the cell boundary.