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Figure 1 Glycoproteomic strategy and hFSH glycosylation characterization. (a) Strategy for the comparative assessment of glycosylation in rhFSH and uhFSH. (b) SDS-PAGE and MALDI-TOF mass spectra of both hFSHs. (c) IEF result (pH gradient: 3–6) of both hFSHs. (d) Sialic acid contents (n=2). Error bars represent SD from duplicate determinants. (e) Mass spectrum of non-glycosylation site at FC#ISINTTWC#AGYC#YTR [(M+3H)3+ at m/z 724.98] without the 0.98 Da increase after PNGase F digestion. #
represents alkylation of cysteine.
Figure 2 Profiling and relative quantification of N-glycans of hFSHs (n=3). (a) HILIC chromatograms of 2-AB-labeled glycans from rhFSH and uhFSH. The structure and relative contents (>2.50%) of glycan are shown and compared. The two or three glycans with highest relative contents are highlighted in red. *The two glycans are present in one peak. (b) Comparison of the N-glycan structures of rhFSH and uhFSH.
