Bacterial and fungal cell membrane lipids

Bacterial and fungal cell membrane lipids are essential structural and functional components that maintain the integrity and permeability of microbial cells (StatPearls, 2023). In bacteria, lipids like phosphatidylglycerol and the precursor Lipid II are critical for membrane stability and cell wall synthesis, while in fungi, ergosterol serves as the primary sterol, performing a role analogous to cholesterol in human cells (PubMed: PMC4220644). These lipids are prime therapeutic targets because of the distinct biochemical differences between microbial and mammalian membranes, which allow for selective toxicity. Drugs such as polyenes (e.g., Amphotericin B) bind directly to ergosterol to create lethal pores, while polymyxins and daptomycin disrupt bacterial membranes through lipid-specific interactions with lipopolysaccharides or acidic phospholipids (PubMed: PMC4941265; PubMed: PMC3122494). Additionally, the biosynthesis pathways for these lipids, such as the ergosterol pathway in fungi, are targeted by azoles and allylamines to inhibit growth and cause cell death. Understanding these lipid targets is crucial for developing new anti-infectives that can bypass existing resistance mechanisms targeting proteins.

Other names

Microbial membrane lipidsErgosterolLipid IIPhospholipidsSterolsLipopolysaccharide (LPS) lipid APhosphatidylglycerol

The mechanism of action involves the disruption of membrane physical integrity through direct binding to induce pore formation and leakage (e.g., polyenes and polymyxins), the inhibition of essential lipid biosynthetic pathways (e.g., azoles inhibiting ergosterol synthesis), or the sequestration of lipid-linked precursors necessary for cell wall assembly (e.g., glycopeptides binding Lipid II) (PubMed: PMC4220644; StatPearls, 2023).