Structural Characterization of Serum N-Glycans by Methylamidation, Fluorescent Labeling, and Analysis by Microchip Electrophoresis.

ABSTRACT: To characterize the structures of N-glycans derived from human serum, we report a strategy that combines microchip electrophoresis, standard addition, enzymatic digestion, and matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS). We compared (i) electrophoretic mobilities of known N-glycans from well-characterized (standard) glycoproteins through standard addition, (ii) the electrophoretic mobilities of N-glycans with their molecular weights determined by MALDI-MS, and (iii) electrophoretic profiles of N-glycans enzymatically treated with fucosidase. The key step to identify the sialylated N-glycans was to quantitatively neutralize the negative charge on both α2,3- and α2,6-linked sialic acids by covalent derivatization with methylamine. Both neutralized and nonsialylat

SUBMITTER: Mitra I 

PROVIDER: S-EPMC5097868 | biostudies-literature | 2016 Sep

REPOSITORIES: biostudies-literature