Mycobacterial membrane phospholipids

Mycobacterial membrane phospholipids are essential structural components of the complex cell envelope of Mycobacterium species, such as Mycobacterium tuberculosis. These lipids, including phosphatidylinositol mannosides (PIMs), phosphatidylethanolamine (PE), and cardiolipin (CL), are critical for maintaining the structural integrity and the extreme impermeability of the mycobacterial cell wall (Jackson, M., 2014, Cold Spring Harb Perspect Med). They serve as the foundation for the plasma membrane and the inner leaflet of the outer mycomembrane, acting as a barrier against host immune responses and antibiotic penetration (Chiaradia, L., et al., 2017, Future Microbiol). Beyond their structural role, phospholipids like PIMs are precursors to major immunomodulatory lipoglycans such as lipoarabinomannan (LAM), which are vital for host-pathogen interactions and the modulation of the host immune system (Morita, Y. S., et al., 2011, Crit Rev Biochem Mol Biol). In disease states like tuberculosis, these phospholipids facilitate the survival of the bacteria within host macrophages by preventing phagosome-lysosome fusion. Therapeutic strategies targeting these phospholipids often involve direct membrane disruption or the inhibition of their biosynthetic pathways, as seen with drugs like clofazimine or experimental antimicrobial peptides (Pal, R., et al., 2021, ACS Infect Dis). However, the similarity between certain bacterial and host phospholipids presents a significant challenge for achieving high selectivity and minimizing systemic toxicity in human patients.

Other names

Mycobacterial lipidsCell wall phospholipidsPhosphatidylinositol mannosidesPIMsMycobacterial membrane lipidsPhosphatidyl-myo-inositol mannosides

Direct disruption of membrane integrity, depolarization of the lipid bilayer, and inhibition of the biosynthesis of essential cell wall components such as lipoarabinomannan.