Fig. 6.

Identification of the N-glycan with 6-sialyl Lewis C. The presumed structure of the N-glycan that was isolated as in Fig. 5 is shown in the upper panel. After β1,3-galactosidase treatment, the galactose-removed sugar chain was collected (middle panel), which still harbored two sialic acids as determined by Mono Q HPLC (Supplementary Fig. S1). Finally, this de-galactosylated sugar chain was treated with neuraminidase and its structure determined by 2D-HPLC mapping. The structure turned out to be A2G0F (lower panel)