Donnelly-Roberts D L, Lentz T L
Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06510.
Brain Res Mol Brain Res. 1991 Sep;11(2):107-13. doi: 10.1016/0169-328x(91)90112-b.
Antibodies were raised in rabbits against synthetic peptides corresponding to loop 2, the 'toxic' loop reacting with the acetylcholine-binding site on the nicotinic acetylcholine receptor, of curaremimetic neurotoxins and the structurally similar segment of the rabies virus glycoprotein. Some of the antibodies cross-reacted with the corresponding peptides confirming the structural similarity between the neurotoxin and glycoprotein peptides. A polyclonal antibody raised against a 29 residue glycoprotein peptide (175-203) in the presence of 0.1% sodium dodecyl sulfate reacted with native alpha-bungarotoxin and rabies virus. Circular dichroism spectroscopy of the 29 residue glycoprotein peptide and a 20 residue king cobra loop 2 peptide (25-44) revealed these peptides to be conformationally similar and composed predominantly of beta sheet structure. These results show the rabies glycoprotein segment is structurally and conformationally similar to neurotoxin loop 2. This similarity may confer on the glycoprotein the capability of interacting with the neurotoxin-binding site on the acetylcholine receptor.
用与筒箭毒样神经毒素的第2环（即与烟碱型乙酰胆碱受体上乙酰胆碱结合位点发生反应的“毒性”环）以及狂犬病病毒糖蛋白结构相似片段相对应的合成肽在兔体内产生抗体。一些抗体与相应肽发生交叉反应，证实了神经毒素和糖蛋白肽之间的结构相似性。在0.1%十二烷基硫酸钠存在的情况下，针对29个残基的糖蛋白肽（175 - 203）产生的多克隆抗体与天然α - 银环蛇毒素和狂犬病病毒发生反应。对29个残基的糖蛋白肽和20个残基的眼镜王蛇第2环肽（25 - 44）进行圆二色光谱分析，结果显示这些肽在构象上相似，且主要由β折叠结构组成。这些结果表明狂犬病糖蛋白片段在结构和构象上与神经毒素第2环相似。这种相似性可能赋予糖蛋白与乙酰胆碱受体上神经毒素结合位点相互作用的能力。
