from Christopher W. Reid writing in Bacterial Glycomics: Current Research, Technology and Applications:
Bacteria and Archaea produce a variety of glycoconjugates such as capsular polysaccharides, lipopolysaccharides, and glycoproteins that are assembled on a polyisoprenyl-phosphate lipid in the cytoplasmic membrane. Traditional methods to analyze the membrane-associated steps of glycan biosynthesis involved the use of metabolic radio-labeling or the indirect detection of lipid-associated glycans. Recent advances in analytical biochemistry now provide the microbial glycobiologist with a number of tools for the direct detection and characterization of low abundance lipid-linked oligosaccharides. Approaches include targeted glycolipidomics strategies, such as affinity-capture capillary electrophoresis mass spectrometry and global approaches such as separation on porous graphite carbon and normal phase liquid chromatography mass spectrometry (LC-MS). These techniques provide opportunities to probe the lipid-associated steps in glycan biosynthesis in greater detail as well as provide an enabling technology for the exploitation of these pathways in glycoengineering.
Further reading: Bacterial Glycomics: Current Research, Technology and Applications