Mass Spectrometric Analysis of Antigenic Determinant Glycans of Soybean Glycoprotein Gly m Bd 30K

Glycosylation of many proteins has been revealed to be closely related to food allergy, and screening and structural analysis of related glycoproteins are essential for studies in this important area. Gly m Bd 30K is one of the major allergens that exist in soybeans. <i>N</i>-Glycans of the Gly m Bd 30K influenced the immunoreactivity and antigen-presenting efficiency. In this paper, soybean allergen glycoprotein Gly m Bd 30K was used as the research object. It was separated and purified by the combination of isoelectric point and Sepharose CL-6B gel. The glycoprotein was analyzed and identified by SDS-PAGE and MALDI-TOF MS. The <i>N</i>-glycans of Gly m Bd 30K glycoprotein were released and labeled by a newly developed one-pot method, and qualitatively and quantitatively analyzed by ESI-MSⁿ and HILIC-UV-MS/MS. The results showed that the purity of Gly m Bd 30K glycoprotein was 95%, and the relative molecular mass was 33,923 Da. The Gly m Bd 30K glycoprotein contained a total of six kinds of glycans, including two types: oligo-mannose type (4.3%) and paucimannose type (95.7%). The paucimannose modified with core α-1,3-fucose and β-1,2-xylose accounted for 92.87%. This study provides quality-reliable materials for the follow-up study of glycan sensitization and also provides a theoretical basis for the in-depth study of the specificity and biological function of the antigenic determinant of Gly m Bd 30K glycoprotein.