Comparative N‑Glycoproteomic Analysis Provides Novel Insights into the Deterioration Mechanisms in Chicken Egg Vitelline Membrane during High-Temperature Storage

The
weakening of chicken egg vitelline membrane (CEVM) is one of
the most important factors influencing egg quality during high-temperature
storage. Therefore, a comparative N-glycoproteomic analysis of CEVM
after 10 days of storage at 30 °C was performed to explore the
roles of protein N-glycosylation in membrane deterioration. In total,
399 N-glycosites corresponding to 198 proteins were identified, of
which 46 N-glycosites from 30 proteins were significantly altered.
Gene ontology analysis revealed that these differentially N-glycosylated
proteins (DGPs) were involved in antibacterial activity, glycosaminoglycan
binding, lipid binding, and aminopeptidase activity. Removal of the
N-glycans in Mucin-5B may result in a loss of CEVM’s mechanical
properties. The N-glycosites enriched in the apolipoprotein B β2
domain in CEVM were significantly changed, which may contribute to
lipid composition modifications during storage. Moreover, N-glycosites
in several metalloproteases were located within the functional domain
or active site region, indicating that the decreased N-glycosylation
levels may affect their structural stability, specific substrate binding,
or enzyme activity. These findings provide novel insights into the
roles of protein N-glycosylation during membrane weakening.