Glycoproteomics reveal differences in site-specific N-glycosylation of whey proteins between donkey colostrum and mature milk

• Published in: Food science & technology Vol. 169; p. 113920
• Main Authors: Guan, Boyuan, Gao, Yang, Chai, Yuxia, Xiakouna, Amantai, Chen, Xinping, Cao, Xueyan, Yue, Xiqing
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.11.2022
• Subjects: Colostrum; Donkey milk; Mature milk; Site-specific glycoproteomics; Whey N-Glycoprotein; Site-specific glycoproteomics; Whey N-Glycoprotein; Colostrum; Mature milk; Donkey milk
• ISSN: 0023-6438; 1096-1127
• DOI: 10.1016/j.lwt.2022.113920

Donkey whey protein has high nutritional value, yet systematic characterisation of site-specific N-glycosylation of donkey whey protein is still in its infancy. This study used label-free site-specific glycoproteomics to identify and quantify 685 intact N-glycopeptides from 135 whey glycoproteins in donkey colostrum (DC) and 384 intact N-glycopeptides from 67 glycoproteins in donkey mature milk (DM). As lactation progressed, 23 site-specific N-glycans mapping to 13 glycosites on 12 glycoproteins were significantly decreased, and 19 site-specific N-glycans mapping to 7 glycosites on 6 glycoproteins were significantly increased. We also found that certain N-glycans attached to the glycosites exhibited significant site specificity. This study provides new insights into the potential relationship between the biological function of donkey whey proteins and their N-glycosylation modifications. Furthermore, the study provides molecular evidence for differences in the site-specific N-glycosylation profile of donkey whey protein during lactation. [Display omitted] •Donkey whey protein site-specific N-glycosylation differs during lactation.•946 N-glycopeptides were identified in 164 donkey whey proteins during lactation.•Heterogeneity of N-glycosylation of donkey whey proteins is outlined.•42 N-glycopeptides of 14 donkey whey proteins differ significantly during lactation.•Structure-activity relationship of donkey whey N-glycoproteins is elucidated.