State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu Province 214122, China; Department of Food Science, University of Massachusetts, Amherst, MA 01003, USA.
Department of Food Science, University of Massachusetts, Amherst, MA 01003, USA.
Food Chem. 2019 Mar 15;276:520-527. doi: 10.1016/j.foodchem.2018.10.032. Epub 2018 Oct 6.
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 α-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.
从中国明对虾中提取的原肌球蛋白（TM）是糖蛋白，研究了去糖基化（酶和化学试剂）和美拉德反应对 TM 构象、变应原性和人细胞致敏性的影响。TM 既有 N-聚糖又有 O-聚糖。去糖基化和糖化后，TM 的α-螺旋减少，而其他二级结构增加。去糖基化增强了 TM 的变应原性和消化率，有助于消化产生较低变应原性的物质，葡萄糖糖化减弱了 TM 的变应原性和消化率，导致消化产生较弱变应原性的物质。胃消化部分降低了消化物的变应原性，肠消化大大降低了消化物的变应原性，胃肠消化最有效地减弱了消化物的变应原性。去糖基化后，去糖基化的 TM 对嗜碱性粒细胞（KU812）的激活作用更强，而葡萄糖糖化的 TM 则削弱了 KU812 的激活作用。去糖基化对结肠细胞（Caco-2）增殖和白细胞介素-8 释放的抑制作用，而葡萄糖糖化的 TM 抑制了 Caco-2 的增殖和白细胞介素-8 的释放。
