CD209L/L-SIGN N-Glycosylation and N-Glycosylation Site Occupancy

CD209L is a membrane glycoprotein with known glycan-binding properties and it also contains 2 N-glycosylation sequons at sites N92 and N361. Treatment with PNGase F in the presence of H218O, which removes N-linked glycans and isotopically labels the formerly-glycosylated site, confirmed that both unmodified and formerly-glycosylated versions of the peptide spanning the N92 N-glycosylated sequon were present. This suggests that a portion of CD209L protein is N-glycosylated at site N92. nUPLC-MS/MS analyses of CD209L digests enabled detection of a glycopeptide consistent with high-mannose type N-linked glycosylation.