College of Food and Biological Engineering, Xiamen Key Laboratory of Marine Functional Food, Fujian Provincial Engineering Technology Research Center of Marine Functional Food, Fujian Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources , Jimei University , Xiamen , Fujian China.
Xiamen Second Hospital , Xiamen , Fujian 361021 , China.
J Agric Food Chem. 2018 Aug 29;66(34):9127-9137. doi: 10.1021/acs.jafc.8b03466. Epub 2018 Aug 21.
Mud crab ( Scylla serrata), which is widely consumed, can cause severe allergic symptoms. Eight linear epitopes and seven conformational epitopes of tropomyosin (TM) from S. serrata were identified using phage display. The conformational epitopes were formed based on the coiled-coil structure of TM. Most of the epitopes were located in the regions where primary structures were conserved among crustacean TM. Twelve synthetic peptides were designed according to the epitopes and trypsin-cutting sites of TM, among them, three synthetic peptides (including one linear epitope and two conformational epitopes) were recognized by all of the patient sera using inhibitory dot blotting. A triple-variant (R90A-E164A-Y267A) was constructed based on the critical amino acids of the TM epitope. The IgE-binding activity of the triple-variant was significantly reduced compared with that of native TM. The results of phage display and site-directed mutagenesis offered new information regarding conformational epitopes of TM.
泥蟹（锯缘青蟹）是一种广泛食用的蟹类，可引起严重的过敏症状。利用噬菌体展示技术鉴定出锯缘青蟹肌球蛋白轻链（TM）的 8 个线性表位和 7 个构象表位。构象表位是基于 TM 的卷曲螺旋结构形成的。大多数表位位于甲壳动物 TM 一级结构保守的区域。根据 TM 的表位和胰蛋白酶切割位点设计了 12 个合成肽，其中 3 个合成肽（包括 1 个线性表位和 2 个构象表位）在抑制斑点印迹中被所有患者血清识别。基于 TM 表位的关键氨基酸构建了三重变体（R90A-E164A-Y267A）。与天然 TM 相比，三重变体的 IgE 结合活性显著降低。噬菌体展示和定点突变的结果为 TM 的构象表位提供了新的信息。
