在母乳养期间,人乳酪蛋白和主要乳清蛋白中的O结合甘化
Martin Nørmark Thesbjerg1, Katrine Overgaard Poulsen1, Julie Astono2
1Department of Food Science, Aarhus University, Agro Food Park 48, DK-8200 Aarhus N, Denmark; Sino-Danish College (SDC), University of Chinese Academy of Science, Huairou District, Beijing 101408, China.
International journal of biological macromolecules
|April 20, 2024
概括
用质谱分析分析了对婴儿健康至关重要的母乳O结合甘氨酸. 尽管酶量下降,但在整个哺乳期内,O链 glycan 水平保持稳定,显示出关键蛋白质的修饰.
科学领域:
- 格莱科米克斯 (Glycomics) 是一个有趣的药物.
- 人类牛奶中的寡糖类.
- 后翻译修改后的修改.
背景情况:
- 糖基化是复杂的,其作用尚未完全理解.
- 人类牛奶 (HM) 糖基化在哺乳期变化,并具有抗微生物和益生菌功能.
- O-链 glycans 是蛋白质中一个显著的翻译后修饰.
研究的目的:
- 用高通量质谱仪识别和分析母乳中的O链 glycans.
- 为了研究乳房期间O-链接糖化模式的变化.
- 探索参与O链糖合成的酶及其与哺乳期的相关性.
主要方法:
- 分析了来自66名捐赠者的184个纵向人乳样本 (3日,1个月1,2,3个分娩后).
- 使用一种转化后修改特定的丰富策略,使用TiO2和ZrO2珠子进行O链 glycopeptide 丰富.
- 采用高通量质谱测量来识别和量化甘氨酸.
主要成果:
- 已识别出主要的O链 glycoproteins,包括β-casein (β-CN),alpha-S1-casein (αS1-CN),kappa-casein (κ-CN),乳酸转移素和专蛋白.
- 在哺乳期观察到某些甘氨基转移酶和甘氨基酶的显着减少,包括O链 glycan 启动剂 (GLNT1,GLNT2).
- 尽管酶水平发生了变化,但在整个哺乳期内,HM的整体O链 glycan水平保持稳定.
- 标志着三种富含的O结合的糖化基因:Gly-Xxx-Xxx-Gly-Ser/Thr,Arg-Ser/Thr,以及Lys-Ser/Thr.
- 在完整的蛋白质和内源性中,在β-CN上发现了独特的O链 glycan 动图.
结论:
- 人类牛奶O链糖化是一种复杂而动态的过程,β-CN是主要载体.
- 尽管酶水平下降,但在整个哺乳期内O链 glycans 的稳定性表明了调节机制.
- 了解这些O链 glycan 结构及其变异,可以了解婴儿营养和健康.
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