Department of Biochemistry, CSIR-Central Food Technological Research Institute (CFTRI), Mysuru, Karnataka, 570020, India.
Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India.
Amino Acids. 2021 Apr;53(4):533-539. doi: 10.1007/s00726-021-02945-5. Epub 2021 Jan 30.
Immunoglobulin G is the abundant antibody present in the colostrum and milk of major dairy animals. In the present study, buffalo milk IgG was characterized for its amino acid sequence and glycan diversity using reverse phase liquid chromatography coupled to ESI-Q-TOF MS in tandem mode. Amino acid sequence analysis of heavy chain constant region revealed the presence of two IgG subtypes namely IgG1 and IgG3, with IgG1 being the abundant. The complete light chain constant region sequence was also determined. N-glycan sequence analysis at a highly conserved site Asn-Ser-Thr revealed the presence of mainly biantennary complex type with core fucosylation (34%), bisecting GlcNAc (19%) and sialylation with both Neu5Ac and Neu5Gc (14%). The observed glycan diversity in buffalo milk IgG is in part comparable with bovine colostrum as well as human, bovine, goat serum counterparts.
免疫球蛋白 G 是在主要乳用动物的初乳和乳汁中丰富存在的抗体。在本研究中，使用反相液相色谱-电喷雾串联四极杆飞行时间质谱联用技术对水牛乳 IgG 的氨基酸序列和聚糖多样性进行了表征。重链恒定区的氨基酸序列分析表明存在两种 IgG 亚型，即 IgG1 和 IgG3，其中 IgG1 较为丰富。还确定了完整的轻链恒定区序列。在高度保守的天冬酰胺-丝氨酸-苏氨酸位点进行 N-糖链序列分析表明，主要存在双天线复杂型，带有核心岩藻糖基化（34%）、双连接 GlcNAc（19%）和 Neu5Ac 和 Neu5Gc 的唾液酸化（14%）。在水牛乳 IgG 中观察到的聚糖多样性在某种程度上可与牛初乳以及人、牛、山羊血清相媲美。
