Department of Biochemistry, CSIR-Central Food Technological Research Institute (CFTRI), Mysuru 570020, Karnataka, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India.
Department of Biochemistry, CSIR-Central Food Technological Research Institute (CFTRI), Mysuru 570020, Karnataka, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India.
Food Chem. 2022 Jul 30;383:132376. doi: 10.1016/j.foodchem.2022.132376. Epub 2022 Feb 9.
Glycans present in glycoproteins are structurally diverse and contribute to the carbohydrate pool of the milk. Goat milk is a leading non-bovine milk source, wherein glycan diversity of several glycoproteins remains unexplored. Herein, site-specific N-glycoprofiling of two major glycoproteins - immunoglobulin G (IgG) and lactoferrin (Lf) from goat milk was performed through RP-UHPLC Q-Tof MS/MS approach. IgG revealed diverse complex glycans that were predominantly biantennary type with differential core fucosylation, bisecting GlcNAc, and mono/di- sialylation (NeuAc/NeuGc). The N-glycan repertoire of Lf at four sites indicated the range of high mannose, complex and hybrid types with varying abundances. High mannose glycans were specifically observed at NNT and NDT sites. Majorly complex glycans with fully sialylated were found at NVT site. While NQT site revealed complex and hybrid types with differential core fucosylation and sialylation. The glycan features observed in these glycoproteins would pave way for effective utilization as bioactive ingredients.
糖蛋白中存在的聚糖结构多样，为乳中的碳水化合物库做出贡献。羊奶是主要的非牛乳来源，其中几种糖蛋白的聚糖多样性仍未得到探索。在此，通过 RP-UHPLC Q-Tof MS/MS 方法对羊奶中的两种主要糖蛋白 - 免疫球蛋白 G（IgG）和乳铁蛋白（Lf）进行了位点特异性 N-糖基化分析。IgG 显示出多种复杂的聚糖，主要为双天线型，具有不同的核心岩藻糖基化、分支 GlcNAc 和单/二唾液酸化（NeuAc/NeuGc）。在四个位点的 Lf 的 N-糖基化谱表明具有不同丰度的高甘露糖、复杂和混合类型的范围。在 NNT 和 NDT 位点特异性观察到高甘露糖聚糖。在 NVT 位点发现了主要带有完全唾液酸化的复杂聚糖。而在 NQT 位点则显示出具有不同核心岩藻糖基化和唾液酸化的复杂和混合类型。在这些糖蛋白中观察到的聚糖特征将为有效利用它们作为生物活性成分铺平道路。
