Fig. 2.

Example zwitterionic and phosphodiester structures. The depicted structures are (i) a methylphosphorylated N-glycan structure from Dictyostelium discoideum, (ii) an N-glycan from Lymantria dispar modified with glucuronic acid and phosphorylcholine, (iii) a schematic honeybee N-glycan, (iv) a schematic glycan from either nematode or cestode species, (v) a phosphoethanolamine-modified N-glycan from Penicillium spp. optionally with an ‘outer chain’ mannose and a bisecting galactofuranose, (vi) two N-glycans with methylaminoethylphosphonate or phosphorylcholine from Volvarina rubella, (vii) glycolipids from insects (example from Drosophila), nematodes and annelids (with phosphorylcholine) and molluscs (with aminoethylphosphonate; also observed with pyruvate and phosphoethanolamine modifications), (viii) a glycosylphosphatidylinositol (GPI) anchor from the Trypanosoma cruzi NETNES protein, (ix) a mucin-type O-glycan from wasp, a mucin-type and a Notch-type from Volvarina rubella, a glycosaminoglycan-like glycan from Oesophagostomum dentatum and (x) phospho-linked sugars from either Dictyostelium discoideum or Entamoeba histolytica. AEP, aminoethylphosphonate; MeAEP, methylaminoethylphosphonate; P, phosphate; PC, phosphorylcholine; PE, phosphoethanolamine; PMe, methylphosphate; Pyr, pyruvate