Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Key Laboratory of Control Technology and Standard for Agro-product Safety and Quality (Ministry of Agriculture), Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China; School of Life Sciences, Discipline of Microbiology, College of Agriculture, Engineering and Science, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban, 4000, South Africa.
Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Key Laboratory of Control Technology and Standard for Agro-product Safety and Quality (Ministry of Agriculture), Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China; School of Food and Biological Engineering, Jiangsu University, Zhenjiang, 212013, China.
Anal Biochem. 2021 Jul 15;625:114222. doi: 10.1016/j.ab.2021.114222. Epub 2021 Apr 28.
The anti-idiotypic antibody is widely used in the field of immunology to simulate structural features or even induce the biological activity of antigens. In this study, we obtained seven anti-idiotypic single-chain variable fragments (scFv) antibodies of Cry2Aa toxin from a phage-displayed mutant library constructed using error-prone PCR technique. A mutant designated 2-12B showed the best binding ability amongst all anti-idiotypic scFv isolates to Plutella xylostella brush border membrane vesicles (BBMVs). 2-12B and Cry2Aa toxin shared a potential receptor of polycalin in P. xylostella BBMVs. Homology modeling and molecular docking demonstrated that 2-12B and Cry2Aa toxin have seven common binding amino acid residues in polycalin. Insect bioassay results suggested that 2-12 had insecticidal efficacy against P. xylostella larvae. These results indicated that the Cry2Aa anti-idiotypic scFv antibody 2-12B partially mimicked the structure and function of Cry2Aa toxin. The anti-idiotypic scFv antibody provides the basic material for the future study of surrogate molecules or new insecticidal materials.
抗独特型抗体广泛应用于免疫学领域，用于模拟抗原的结构特征甚至诱导其生物活性。在这项研究中，我们使用易错 PCR 技术构建的噬菌体展示突变文库中获得了 7 种 Cry2Aa 毒素的抗独特型单链可变片段（scFv）抗体。一个名为 2-12B 的突变体在所有抗独特型 scFv 分离物中表现出与小菜蛾刷状缘膜囊泡（BBMVs）结合能力最强。2-12B 和 Cry2Aa 毒素在 P. xylostella BBMVs 中具有共同的多钙连蛋白受体。同源建模和分子对接表明，2-12B 和 Cry2Aa 毒素在多钙连蛋白中有 7 个共同的结合氨基酸残基。昆虫生物测定结果表明，2-12B 对小菜蛾幼虫具有杀虫活性。这些结果表明，Cry2Aa 抗独特型 scFv 抗体 2-12B 部分模拟了 Cry2Aa 毒素的结构和功能。抗独特型 scFv 抗体为替代分子或新型杀虫材料的未来研究提供了基础材料。
