Epitopes of the cholera family of enterotoxins.
Epitopes of the cholera family of enterotoxins.
复制标题
霍乱肠毒素家族的表位。
DOI：
10.1093/clinids/9.3.544
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发表时间：
1987
期刊：
影响因子：
--
通讯作者：
Ludwig,DS
中科院分区：
文献类型：
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作者：
Finkelstein,RA;Burks,MF;Zupan,A;Dallas,WS;Jacob,CO;Ludwig,DS
杂交瘤衍生的单克隆抗体针对霍乱家族的肠毒素和嵌合b亚基蛋白，其中来自猪源大肠杆菌（P-LT）的不耐热的霍乱相关肠毒素的单个氨基酸残基被来自anE的这种肠毒素的相应残基所取代。人源大肠杆菌（H-LT）。发现单氨基酸取代对蛋白质的理化行为和免疫反应性有深远的影响。利用酶联免疫吸附试验（elisa），用不同的单克隆抗体鉴定出gm1结合域的几个不同的表位。兔抗霍乱肠毒素B亚基合成肽的多克隆血清与文库中两种不同的霍乱肠毒素、两种h - lt、P-LT和四种嵌合蛋白有不同程度的交叉反应。其中一些反应被GM1神经节苷脂阻断，而不是被GM1的寡糖阻断，这一发现表明，肽产生的抗体靠近GM1结合域，而不是在GM1结合域内。基于已报道的各种肠毒素的氨基酸序列，构建了一个假设的进化树。随着其他肠毒素的描述，确定它们是否和在哪里适合这个方案将是有趣的。
Hybridoma-derived monoclonal antibodies were raised to enterotoxins of the cholera family and to chimeric B-subunit proteins in which individual amino acid residues of a heatlabile, cholera-related enterotoxin from anEscherichia colistrain ofporcine origin (P-LT) were substituted with corresponding residues from such an enterotoxin from anE. colistrain of human origin (H-LT). Single amino acid substitutions were found to have profound effects on the physicochemical behavior of the proteins and on their immunologic reactivity.With the use of enzyme-linked immunosorption assays (ELISAs) with and without the GMtganglioside receptor for these toxins, several distinct epitopes in GM1-binding domains were identified by different monoclonal antibodies. Polyclonal rabbit antisera to synthetic peptides of the cholera enterotoxin B subunit were cross-reactive to various degrees with the proteins in our library, which include two different cholera enterotoxins, two H-LTs, P-LT, and four chimeric proteins. Some of these reactions were blocked by GM1ganglioside but not by the oligosaccharide of GM1, a finding suggesting that the peptides generated antibodies to epitopes near, but not in, a GMt-binding domain. A hypothetical evolutionary tree based on the reported amino acid sequences of the various enterotoxins is constructed. As additional enterotoxins are described, it will be interesting to determine if and where they fit in this scheme.