Conformation, allergenicity and human cell allergy sensitization of tropomyosin from Exopalaemon modestus: Effects of deglycosylation and Maillard reaction

Tropomyosin (TM) from Exopalaemon modestus was glycoprotein, the effects of deglycosylation (enzyme and chemical regents) and Maillard reaction on the conformation, allergenicity and human cell sensitization of TM were investigated. TM had both N-glycan and O-glycan. After deglycosylation and glycation, the alpha-helix of TM reduced, while other secondary structures promoted. Deglycosylation enhanced TM allergenicity and digestibility, contributed to digests with lower allergenicity, glucose glycation weakened the allergenicity and digestibility of TM, led to digests with weaker allergenicity. Gastric digestion partly reduced allergenicity of digests, intestinal digestion highly reduced digests' allergenicity, gastrointestinal digestion most efficiently weakened the allergenicity of digests. After deglycosylation, the deglycosylated TM exerted stronger activation of basophil (KU812), while glucose glycated TM weakened KU812 activation. Deglycosylation exerted inhibition on colon cell (Caco-2) proliferation and increase of IL-8 release, while glucose glycated TM suppressed Caco-2 proliferation and IL-8 release.