摘要
目的 采用生物信息学软件分析棘球绦虫主要虫卵抗原(MEAs)蛋白的分子特性。方法 从NCBI蛋白质数据库中下载棘球绦虫MEAs蛋白的氨基酸序列,采用ProtParam、NetSolP-1.0、SignalP-5.0、TMHMM 2.0、ProtComp 9.0、Structure、NetPhos 3.1、BCPREDS等在线分析程序预测理化性质、在大肠杆菌中的表达特性、信号肽、跨膜结构域、亚细胞定位、保守结构域、磷酸化位点及B细胞表位,并通过MEGA 6.06程序对不同物种来源的MEAs蛋白构建进化树。结果 对11条棘球绦虫MEAs蛋白序列进行分析,序列长度为314~503 aa,等电点为5.73~7.26,分子量为35 843.76~54 356.24;在大肠杆菌中表达的可溶性为0.488 0~0.563 2,可用性为0.254 5~0.283 5;均具有典型的α晶体结构域,属于HSP20超家族;均含有丝氨酸磷酸化位点、苏氨酸磷酸化位点和酪氨酸磷酸化位点;均不存在信号肽序列及跨膜结构域,为非分泌、非跨膜蛋白;主要定位于胞质、胞核,在线粒体、胞外和质膜上也有分布;棘球绦虫MEAs蛋白优势B细胞抗原表位的数量为1~3。不同物种来源的MEAs蛋白分为两大枝,其中EmMEAp40_1、EgMEA_4、EgMEAp40_1与微小膜壳绦虫MEAp40等聚为一枝,其余8条棘球绦虫MEAs蛋白与日本血吸虫MEAs等聚为一枝。结论 通过生物信息学软件筛选了棘球绦虫MEAs蛋白的优势B细胞抗原表位,为进一步研究棘球绦虫MEAs蛋白的生物学功能提供参考。
Objective To analyze the molecular characteristics of major egg antigens(MEAs) from Echinococcus granulosus and Echinococcus multilocularis with bioinformatic software.Methods The amino acid sequences of MEAs from Echinococcus granulosus and Echinococcus multilocularis were downloaded from the protein database on NCBI.Bioinformatic tools,such as ProtParam,NetSolP-1.0,SignalP-5.0,TMHMM 2.0,ProtComp 9.0,Structure,NetPhos 3.1,BCPREDS,were used to analyze the physicochemical characteristics,expression properties in E.coli,signal peptide,transmembrane domain,subcellular localization,conserved structural domains,phosphorylation sites,and B cell epitopes of MEAs from Echinococcus granulosus and Echinococcus multilocularis.Phylogenetic tree construction of MEAs from various species was performed using MEGA 6.06.Results 11 MEAs were coded by 314-503 aa,with the isoelectric point of 5.73-7.26,the molecular weight of 35 843.76-54 356.24.The solubility and availability of expression in E.coli was 0.488 0-0.563 2,and 0.254 5-0.283 5 respectively.Typical α-crystal domains were found in all 11 MEAs,indicating that MEAs from Echinococcus granulosus and Echinococcus multilocularis belongs to the HSP20 superfamily.Serine phosphorylation sites,threonine phosphorylation sites and tyrosine phosphorylation sites were found in all 11 MEAs.Signal peptide sequence and transmembrane domains were not be found in all 1 1 MEAs,indicating that MEAs from Echinococcus granulosus and Echinococcus multilocularis belonged to nonsecretory and non-transmembrane proteins.11 MEAs mainly located in cytoplasm and nucleus,and also distributed in mitochondria,extracellular and plasma membrane.The number of dominant B cell epitopes of MEAs from Echinococcus granulosus and Echinococcus multilocularis was 1-3.MEAs proteins from different species were divided into two branches,among which EmMEAp40,EgMEA,EgMEAp40and Hymenolepis microstoma MEAp40 were clustered into one branch,and the other eight MEAs proteins were clustered into one branch with Schistosoma japonicum MEAs.Conclusion Bioinformatics software is used to screen the dominant B cell epitopes of MEAs proteins from Echinococcus granulosus and Echinococcus multilocularis,which provide references for the further study of biological functions of MEAs proteins from Echinococcus granulosus and Echinococcus multilocularis.
作者
李庆贺
张家耀
樊斌
王芬
LI Qing-he;ZHANG Jia-yao;FAN Bin;WANG Fen(Central Hospital of Enshi Tujia and Miao Autonomous Prefecture,Enshi,Hubei 445000,China;Suining Central Hospital,Suining,Sichuan 629000,China)
出处
《中国热带医学》
CAS
2022年第7期611-616,共6页
China Tropical Medicine
基金
湖北省卫生计生委科研项目(No.WJ2019M103)
2019年遂宁市青年科技人才托举工程项目(遂科协发[2019]11号)。
