Whey is a liquid material created as a by-product of cheese production, and an essential source of dietary nutrients, used in dairy foods for infants. Whey protein is a mixture of globular proteins isolated from whey. An advanced isobaric tags for relative and absolute quantitation (iTRAQ) mass spectrometry proteomic approach was used, to analyze differentially expressed whey proteins in human and bovine colostrum and mature milk.
The study published in the International Journal of Food Sciences and Nutrition showed a total of 584 whey proteins in human and bovine colostrum and mature milk identified and quantified by the isobaric tag for relative and absolute quantification (iTRAQ) proteomic method. The 424 differentially expressed whey proteins were identified and analysed according to gene ontology (GO) annotation, Kyoto encyclopaedia of genes and genomes (KEGG) pathway, and multivariate statistical analysis. Biological processes principally involved biological regulation and response to stimulus.
Major cellular components were extracellular region part and extracellular space. The most prevalent molecular function was protein binding. Twenty immune-related proteins and 13 proteins related to enzyme regulatory activity were differentially expressed in human and bovine milk. Differentially expressed whey proteins participated in many KEGG pathways, including major complement and coagulation cascades and in phagosomes.
Whey proteins show obvious differences in expression in human and bovine colostrum and mature milk, with consequences for biological function. The results in the study conducted by a team of scientists at the College of Food and Science Shenyang Agricultural University increased our understanding of different whey proteomes, which could provide useful information for the development and manufacture of dairy products and nutrient food for infants.
For the full journal article see the reference below:
Yang, M., Cao, X., Wu, R., Liu, B., Ye, W., Yue, X., & Wu, J. (2017). Comparative proteomic exploration of whey proteins in human and bovine colostrum and mature milk using iTRAQ-coupled LC-MS/MS. International Journal of Food Sciences and Nutrition, 1-11. doi:10.1080/09637486.2017.1279129