Golshani Maryam, Oloomi Mana, Bouzari Saeid
Molecular Biology Department, Institute Pasteur of Iran, Pasteur Ave., Tehran, 13164, Iran.
In Silico Pharmacol. 2016 Dec;5(1):2. doi: 10.1007/s40203-017-0022-4. Epub 2017 May 22.
Shiga toxins belong to a family of structurally and functionally related toxins serving as the main virulence factors for pathogenicity of the Shiga toxin-producing Escherichia coli (STEC) associating with Hemolytic uremic syndrome (HUS). At present, there is no effective treatment or prevention for HUS. The aim of the present study was to find conserved regions within the amino acid sequences of Stx1, Stx2 (Shiga toxin) and their variants. In this regard, In-silico identification of conformational continuous B cell and T-cell epitopes was performed in order to introduce new potential vaccine candidates. 93-100% Homology was observed in Stx1 and its variants. In Stx2 and its variants, 69-100% homology was shown. By sequence alignment with Stx1 and Stx2, 54% homology was detected. T-cell epitope identification in Stx1A and Stx2A epitopes with highest binding affinity for each HLA (human leukocyte antigen) was demonstrated with 100% identity among all Stxs. B-cell epitope prediction was resulted in finding of four common epitopes between Stxs. In silico analysis of Stxs was resulted to identification of new peptide targets that could be used in development of new epitope vaccine candidates or in immunodiagnostic tests.
志贺毒素属于一类在结构和功能上相关的毒素，是产志贺毒素大肠杆菌（STEC）致病性的主要毒力因子，与溶血尿毒综合征（HUS）相关。目前，对于HUS尚无有效的治疗或预防方法。本研究的目的是在Stx1、Stx2（志贺毒素）及其变体的氨基酸序列中寻找保守区域。在这方面，进行了基于计算机的构象连续B细胞和T细胞表位鉴定，以引入新的潜在疫苗候选物。在Stx1及其变体中观察到93 - 100%的同源性。在Stx2及其变体中，显示出69 - 100%的同源性。通过与Stx1和Stx2进行序列比对，检测到54%的同源性。对每种HLA（人类白细胞抗原）具有最高结合亲和力的Stx1A和Stx2A表位中的T细胞表位鉴定表明，所有Stxs之间具有100%的同一性。B细胞表位预测结果发现了Stxs之间的四个共同表位。对Stxs的计算机分析导致鉴定出可用于开发新的表位疫苗候选物或免疫诊断测试的新肽靶标。
