Characterizaton Of N-Glycan Structure And N-Glycosylation Of Ginger Glycoproteins

Glycoprotein is a molecule composed of oligosaccharide chains covalently linked with proteins and carbohydrate is an important component of glycoprotein playing an irreplaceable role.In this paper,ginger glycoproteins were used as an experimental material,enriched by magnetic particles and released the N-glycan by PNGase F and PNGase A.The structure of N-linked glycan and glycosylation sites are analyzed by MS in detail and the physiological activities of ginger glycoprotein were analyzed combining with KEGG pathway.The study provided reference for study on biological function of ginger glycoproteins.The main results obtained are summarized as follows.1.Lectin microarray magnetic particles were used to enrich ginger-derived glycoproteins.The result showed that five types of lectin e.g.VVA,ConA,STL,LEL,and LCA could specifically bind with ginger-derived glycoproteins.It indicated that the glycan structure of the ginger-derived glycoproteins contains core fucose,mannose,GlcNAc.2.The total glycan,N-glycan enriched by ConA and N-glycan enriched by STL relaesed from ginger glycoproteins were identified by MALDI-TOF-MS.The results showed that the number of complex type glycan in the three kinds of sample was siginificant higer than high-mannose and hybide type glycan.Mannose,Fucose,Xylose and N-GlcNAc were the common oligosaccharide in the ginger glycoproteins,and existed the large number of fucosylated N-glycan.3.The glycosylation sites were analyzed using HPLC-MS/MS and bioinformatics analysis of these glycoproteins was performed by KEGG.The result showed that a total of 10 N-glycosylation sites were characterized using the Uniprot database.The 10 identified glycopeptides belong to different glycoproteinswith different biological activities,and six of them related to important bio-processes.CK2? participates in the circadian rhythm of plant.COG complex,which plays an important role in the modification and processing of glycoproteins in Golgi,and Topo 2,which affects DNA replication,transcription and other physiological activities.In this paper,we can provide a basis for the analysis of glycosylation sites of glycoproteins and comprehend the relationship between the structure and the activities of glycoproteins.