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a lypid with sugar chain(s) (glycans) attached. Aype of glycoconjugate (molecule with sugar attached to something). There are several different subclasses of them  with different names (of course…) These include lipopolysaccharides, glycosylphosphatidylinositol (GPI), cerebrosides, & gangliosides. ⠀

Lipopolysaccharide (LPS) is a glycolipid present in bacteria’s outer membrane, with different bacterial species having different sugar combos in their LPS. These sugars provide Gram-negative bacteria (ones w/o a strong cell wall) with a barrier that makes it hard for would-be attackers to get to the membrane itself (and potentially into the bacteria). So it serves to help protect the bacterial membrane from things like antimicrobial molecules and viruses. But not humans – our immune system recognizes LPS and attacks it. May sound great, but too much LPS can cause septic shock (a sort of immune system overreaction when bacteria are in your blood). You might have heard of LPS by another name – endotoxin – just like that nickname suggests, LPS is toxic to our bodies and is responsible for some of those symptoms of bacterial infections people experience – this includes fever (LPS is a fever-inducer aka pyrogen). To prevent over-reaction we have enzymes that can break it down⠀

Glycosylphosphatidylinositol (GPI) is a short sugar chain that serves to anchor non-membrane-spanning proteins to the outside of the cell. One end of the sugar links to a phospholipid head and the other end hooks up (through a phosphoethanolamine linker) to a protein. So, with a GPI-anchored protein you have lipids, carbs, & proteins all working together! Molecular teamwork is so cool! Our bodies use a bunch of these proteins to do a bunch of different things including helping cells recognize each other and acting in signal pathways. ⠀

Cerebrosides & gangliosides are glycolipids that I’m not sure what do but there’s a bunch of them in nervous tissues & if there are problems making or breaking them you get issues. ⠀