牛乳中不同部分蛋白质的组成及功能分析

本研究通过SDS-PAGE电泳将牛乳中不同蛋白质组成部分进行分离鉴定发现,乳脂肪球膜中存在201种蛋白,乳清中存在96种蛋白,酪蛋白中存在21种蛋白,乳粒中存在43种蛋白,其中有27种相同表达的蛋白。通过GO功能注释分析发现,在生物过程中乳脂肪球膜蛋白发挥的作用大于乳清、乳粒蛋白,尤其是生物的调控作用;在分子功能上,牛乳蛋白的主要分子功能是结合作用,其中乳脂肪球膜蛋白的结合作用最强;而乳粒蛋白参与的转运活性分子功能大于乳脂肪球膜、乳清蛋白。在细胞组成上,与乳清、乳粒蛋白相比乳脂肪球膜蛋白参与的细胞组成均较多,而在细胞膜的组成上乳粒蛋白参与较多。通过京都基因与基因组百科全书(KEGG)代谢通路分析可知,乳脂肪球膜、乳清、乳粒中的蛋白均参与过氧化物酶体增殖物激活受体信号通路。对牛乳蛋白质组成进行研究,不仅能够增加牛乳的利用率,并且为日后以乳脂肪球膜、乳粒蛋白作为原料生产乳制品提供理论依据。

Analysis of the Composition and Function of Different Part Protein in Milk

In this study, SDS-PAGE was used for separating of different component protein parts in milk, and mass spectrometry was used for identifying. It found that there were 201 kinds of protein in milk fat globule membrane, 96 kinds of protein in whey, and 43 kinds of protein in exosome and in these proteins, there were 27 kinds of the same expression protein. It found that the function of milk fat globule protein in the process of biological process was higher than whey protein and milk exosome protein, especially in biological regulation through the functional analysis of GO. In the molecular function, the main molecular function of different proteins in milk is the combination, and the function of milk fat globule proteins is the strongest. Exosome proteins involved in the molecule function of transport activity are greater than the milk fat globule membrane and whey proteins. Milk exosome involving in more cellular composition is the membrane, compared with whey and milk exosome, MFGM protein involved in cellular composition are more. KEGG pathway analysis shown that milk fat globule membrane, whey, milk exosome involved in metabolic pathways are not the same, metabolic pathways involved in the three parts was the peroxisome proliferator-activated receptor signaling pathway. Studying on milk protein can not only increase the utilization rate of milk, and the milk fat globule membrane, milk protein particles could provide a theoretical basis for producing dairy products as a raw material in the future.