Bacterial cell membrane phospholipids and surface anionic groups

Bacterial cell membrane phospholipids and surface anionic groups constitute the fundamental structural and functional barrier of the bacterial cell. Unlike mammalian membranes, which are rich in neutral phospholipids and cholesterol, bacterial membranes contain high proportions of negatively charged lipids such as phosphatidylglycerol and cardiolipin, as well as surface-exposed anionic polymers like lipopolysaccharides in Gram-negative bacteria or teichoic acids in Gram-positive bacteria (Nature Reviews Microbiology, 2017). These components are vital for maintaining the cell's electrochemical gradient, protecting against environmental stressors, and facilitating the assembly of membrane proteins (PubMed, 2021). In clinical medicine, these anionic structures serve as primary targets for several classes of last-resort antibiotics, including polymyxins and lipopeptides. These drugs exploit the charge difference between bacterial and host cells to selectively bind, insert into the membrane, and cause rapid depolarization or physical rupture, leading to bacterial death (NIH, 2022). Understanding these targets is crucial for developing new antimicrobial agents that can overcome increasing rates of antibiotic resistance (StatPearls, 2023).

Other names

Bacterial membrane lipidsAnionic phospholipidsPhosphatidylglycerolCardiolipinBacterial cell envelope anionic componentsSurface anionic groups

Drugs targeting these components typically utilize electrostatic attraction to bind to negatively charged surface groups, followed by hydrophobic insertion into the lipid bilayer. This process leads to membrane permeabilization, pore formation, or physical disruption of the membrane, resulting in the leakage of intracellular contents, loss of membrane potential, and eventual cell lysis (StatPearls, 2023; PubMed, 2021).