Loh L C, Qualtiere L F
Department of Microbiology, University of Saskatchewan, Saskatoon, Canada.
Virology. 1988 Feb;162(2):498-502. doi: 10.1016/0042-6822(88)90495-3.
An 87K glycoprotein (gp87) on the murine cytomegalovirus (MCMV) virion was immunoprecipitated by the neutralizing monoclonal antibody (MAb) 8D1.11A. The 87K glycoprotein is also radiolabeled in a surface iodination reaction, suggesting that it is exposed on the surface of the virion. Using a nondenaturing system of polyacrylamide gel electrophoresis in combination with Western blotting, we have shown that the epitope recognized by the MAb 8D1.11A resides on gp87. The failure of 8D1.11A to react with gp87 in a reduced and denatured form suggests that the epitope is recognized only when disulfide linkages are preserved. Our data also indicated that gp87 is present in the MCMV virion both in a monomeric form and as a component of disulfide-linked complexes. Using a two-dimensional gel electrophoresis system, we have demonstrated the presence of disulfide linkages between gp87 and virion polypeptides with apparent molecular weights of 138K, 46K, and 20K. Finally, the difference in migration rates of gp87 in SDS-polyacrylamide gels under reducing and nonreducing conditions suggests the existence of intramolecular disulfide bonds.
小鼠巨细胞病毒（MCMV）病毒粒子上的一种87K糖蛋白（gp87）可被中和性单克隆抗体（MAb）8D1.11A免疫沉淀。87K糖蛋白在表面碘化反应中也会被放射性标记，这表明它暴露在病毒粒子表面。通过使用聚丙烯酰胺凝胶电泳的非变性系统结合蛋白质免疫印迹法，我们已证明MAb 8D1.11A识别的表位位于gp87上。8D1.11A不能与还原和变性形式的gp87发生反应，这表明该表位只有在二硫键得以保留时才能被识别。我们的数据还表明，gp87以单体形式以及作为二硫键连接复合物的组分存在于MCMV病毒粒子中。通过使用二维凝胶电泳系统，我们已证明gp87与表观分子量为138K、46K和20K的病毒粒子多肽之间存在二硫键。最后，gp87在还原和非还原条件下在SDS - 聚丙烯酰胺凝胶中的迁移率差异表明存在分子内二硫键。
