Effects of Glycosylation Combined with Phosphate Treatment on the Allergenicity and Structure of Tropomyosin in <i>Litopenaeus vannamei</i>
Qifei Sun, Fei Xia, Mengsi Li, Huilin Zhang, Yu-Ni Liao, Qing-Mei Liu, Meng Liu, Gui-Xia Chen, Lian-zhong Luo, Guang‐Ming Liu
Abstract
Tropomyosin (TM) is the main allergen in shrimp ( Litopenaeus vannamei ). In this study, the effects of allergenicity and structure of TM by glycosylation (GOS-TM), phosphate treatment (SP-TM), and glycosylation combined with phosphate treatment (GOS-SP-TM) were investigated. Compared to GOS-TM and SP-TM, the IgG/IgE binding capacity of GOS-SP-TM was significantly decreased with 63.9 ± 2.0 and 49.7 ± 2.7%, respectively. Meanwhile, the α-helix content reduced, surface hydrophobicity increased, and 10 specific amino acids (K 30, K 38, S 39, K 48, K 66, K 74, K 128, K 161, S 210, and K 251 ) were modified by glycosylation on six IgE linear epitopes of GOS-SP-TM. In the BALB/c mice allergy model, GOS-SP-TM could significantly reduce the levels of specific IgE, IgG1, and CD4 + IL-4 +, while the levels of IgG2a, CD4 + CD25 + Foxp3 +, and CD4 + IFN-γ + were increased, which equilibrated Th1 and Th2 cells, thus alleviating allergic symptoms. These results indicated that glycosylation combined with phosphate treatment can provide a new insight into developing hypoallergenic shrimp food.