Immunoglobulin E Epitope Mapping and Structure-Allergenicity Relationship Analysis of Crab Allergen Scy p 9.
Xin-Rong HeYang YangYe-Xin ChenShuai KangFa-Jie LiDong-Xiao LiQing-Mei LiuGui-Xia ChenXiao-Mei ChenGuang-Ming LiuPublished in: Journal of agricultural and food chemistry (2023)
Filamin C is an allergen of Scylla paramamosain (Scy p 9), and six IgE linear epitopes of the allergenic predominant region had previously been validated. However, the IgE epitope and structure-allergenicity relationship of Scy p 9 are unclear. In this study, a hydrophobic bond was found to be an important factor of conformation maintaining. The critical amino acids in the six predicted conformational epitopes were mutated, and the IgE-binding capacity and surface hydrophobicity of four mutants (E 216 A, T 270 A, Y 699 A, and V 704 A) were reduced compared to Scy p 9. Ten linear epitopes were verified with synthetic peptides, among which L-AA 187-205 had the strongest IgE-binding capacity. In addition, IgE epitopes were mapped in the protruding surface of the tertiary structure, which were conducive to binding with IgE and exhibited high conservation among filamin genes. Overall, these data provided a basis for IgE epitope mapping and structure-allergenicity relationship of Scy p 9.