In depth N-glycoproteomics shows glyco-features of chicken egg white

Abstract

Chicken egg white proteins have been studied using proteomic approaches. Some glycomic studies of isolated egg white proteins and of the complex egg white have been reported. However, no detailed glycoproteomic studies on the whole egg white have been performed so far to simultaneously characterize the modified peptides along with their glycan moieties. In this study, using a nanoHPLC-ESI-Orbitrap-HCD analysis, glycoproteins from chicken egg white were studied in a single experiment using a three-step workflow. Using this glycoproteomic approach, 19 glycoproteins were characterized. Among them, glycosylation sites and their linked glycan structures in 6 low abundance proteins (heat shock cognate 71 kDa protein, vimentin (fragment), E1BY93 uncharacterized protein, transforming growth factor beta-2 proprotein, ITA6_CHICK integrin alpha-6 and VIT2_CHICK vitellogenin-2) were obtained. Chicken egg white is an easily available source of high quality proteins in the human diet. However, there are reports describing protein-induced allerginicity associated with egg consumption probably due to glycosylated proteins. This new characterization will be useful for the development of appropriate processing methods to decrease the adverse health effects of glycoproteins and expand egg white nutraceutical applications.