Characterization and comparison of milk fat globule membrane N-glycoproteomes from human and bovine colostrum and mature milk.

Human and bovine milk fat globule membrane (MFGM) proteins have been identified and characterized; however, their glycosylation during lactation remains unclear. We adopted a glycoproteomics approach to profile and compare MFGM N-glycoproteomes in human and bovine milk during lactation. A total of 843, 718, 614, and 273 N-glycosite peptides corresponding to 465, 423, 334, and 176 glycoproteins were identified in human colostrum, human mature milk, bovine colostrum, and bovine mature milk, respectively. The biological functions of these MFGM N-glycoproteins were revealed through bioinformatics. Substantial differences were observed between human and bovine milk, and immune-related MFGM N-glycoproteins varied between colostrum and mature milk from both species. Our results expand current knowledge of MFGM N-glycoproteomes, and further demonstrate the complexity and biological functions of MFGM N-glycosylation. These data can provide references for the application of bovine MFGM N-glycoproteins in infant formula to resemble human milk and in functional foods.