Integrated analysis of natural glycans using a versatile pyrazolone-type heterobifunctional tag ANPMP

Glycans mediate various biological processes through carbohydrate-protein interactions, and glycan microarrays have become indispensable tools for understanding these mechanisms. However, advances in functional glycomics are hindered by the absence of convenient and universal methods for obtaining natural glycan libraries with diverse structures from glycoconjugates. To address this challenge, we have developed an integrative approach that enables one-pot release and simultaneously capture, separation, structural characterization, and functional analysis of N/O-glycans. Using this approach, glycoconjugates are incubated with a pyrazolone-type heterobifunctional tag-ANPMP to obtain glycan-2ANPMP conjugates, which are then converted to glycan-AEPMP conjugates. We prepared a tagged glycan library from porcine gastric mucin, soy protein, human milk oligosaccharides, etc. Following derivatization by N-acetylation and permethylation, glycans were subjected to detailed structural characterization by ESI-MSn analysis, which revealed >83 highly pure glycan-AEPMPs containing various natural glycan epitopes. A shotgun microarray is constructed to study the fine details of glycan-bindings by proteins and antisera.