removal carbohydrates cell surfaces - how to "shave off" sugars from cell surfaces (May/18/2006 )
I am studying cell-cell adhesion with isolated blastomeres. I would like to test the role
of carbohydrates in this adhesion by "shaving" the cells off most (if not all) their
sugar residues (from glycolipids and glycoproteins) and then test these cells for
adhesion defects. Does any of you have any recommendation whether I should use glycosidases (and which) or swamp the media with a competitive lectin/other stuff?
Glycosidases will chomp off bits of the sugars, not neccesarily all. If you still get binding how will you know what residues play a part?
Lectins will bind to the sugar coated cells. If the lectins are "free" at the other end, you simply block binding sites. Nothing novel there. Wont the lectins be a steric hindrance to cell binding..you wont be able to say if it's absence of sugar or presence of lectin that inhibits binding.
If the lectins are anchored (conjugated to proteins bound to the sides of the well/test tube etc) surely the cells will just adhere. Not sure how that helps you.
I did some work on bacterial toxin binding to nerve cells. We found that the toxin had protein-protein binding sites and sugar-protein sites. We analysed the sugar sites by x-ray crystallography. I think that would help you. We soaked the toxin in carbohydrate residue solution and looked at the 3D structure of both receptor and sugar. Worked a treat and was a fascinating project.