Fig. 5.

Compiled structures of N-glycans identified on 23 N-glycosites of S protein. Studies were summarized only when the reported N-glycans were characterized by fragment ions in MS2 spectra that can help deduce their structures or N-glycans were exhibited with annotations to reveal their exact structures. A little ambiguousness in N-glycan structures such as uncertain position of terminal monosaccharide are allowed. Studies that reported N-glycans with only monosaccharide compositions were not placed in this figure