Progress in Characterization of Lipopolysaccharides and Lipid A by Mass Spectrometry.

Lipopolysaccharides (LPS) are complex molecules embedded in the outer membrane of Gram-negative bacteria. LPS are highly heterogeneous across species and strains, posing a significant analytical challenge. This review article explores recent advances in the identification and characterization of LPS, with a particular focus on the role of mass spectrometry (MS) techniques. The review highlights how MS, in conjunction with various separation methods and spanning different ionization techniques and dissociation modes, has enabled more precise and sensitive determination of LPS composition, with a focus on lipid A structure. Finally, emerging trends in MS applications for LPS research are discussed and its potential to provide deeper insights into the development of antibiotic resistance among pathogenic bacteria.