Babu J P, Abraham S N, Dabbous M K, Beachey E H
Infect Immun. 1986 Oct;54(1):104-8. doi: 10.1128/iai.54.1.104-108.1986.
A 60-kilodalton glycoprotein previously isolated and purified from human saliva (J. B. Babu, E. H. Beachey, D. L. Hasty, and W. A. Simpson, Infect. Immun. 51: 405-413, 1986) was found to interact with type 1 fimbriae and prevent adhesion of type 1 fimbriated Escherichia coli to animal cells in a D-mannose-sensitive manner. Purified salivary glycoprotein agglutinated type 1 fimbriated E. coli and, at subagglutinating concentrations, blocked the ability of type 1 fimbriated E. coli to attach to human buccal epithelial cells or agglutinate guinea pig erythrocytes. Both interactions were inhibited by alpha-methyl-D-mannoside but not by alpha-methyl-D-glucoside. Complexing of the glycoprotein to type 1 fimbriae was demonstrated by molecular sieve chromatography and modified Western blots. When mixed with type 1 fimbriae, the radiolabeled salivary glycoprotein coeluted with type 1 fimbriae from a column of Sepharose 4B. When blotted from a sodium dodecyl sulfate gel to nitrocellulose sheets, the glycoprotein interacted directly with type 1 fimbriae applied to the blots. Both of the latter interactions also were blocked by alpha-methyl-D-mannoside but not by alpha-methyl-D-glucoside. Chemical modification of the glycoprotein with sodium metaperiodate abolished its ability to interact with isolated type 1 fimbriae or type 1 fimbriated E. coli. These results suggest that the carbohydrate moiety of the 60-kilodalton glycoprotein serves as a receptor for type 1 fimbriae in the oral cavity, and we postulate that the interaction may cause agglutination and early removal of E. coli, thereby preventing colonization by these organisms of oropharyngeal mucosae and dental tissues.
先前从人唾液中分离并纯化出的一种60千道尔顿糖蛋白（J. B. 巴布、E. H. 比奇、D. L. 哈斯蒂和W. A. 辛普森，《感染与免疫》51: 405 - 413, 1986）被发现可与1型菌毛相互作用，并以D - 甘露糖敏感的方式阻止1型菌毛化大肠杆菌黏附于动物细胞。纯化的唾液糖蛋白可凝集1型菌毛化大肠杆菌，在亚凝集浓度下，可阻断1型菌毛化大肠杆菌黏附于人颊黏膜上皮细胞或凝集豚鼠红细胞的能力。这两种相互作用均被α - 甲基 - D - 甘露糖苷抑制，但不被α - 甲基 - D - 葡萄糖苷抑制。通过分子筛色谱法和改良的蛋白质印迹法证实了该糖蛋白与1型菌毛的结合。当与1型菌毛混合时，放射性标记的唾液糖蛋白与1型菌毛从琼脂糖4B柱上共同洗脱。当从十二烷基硫酸钠凝胶印迹到硝酸纤维素膜上时，该糖蛋白与印迹上的1型菌毛直接相互作用。后两种相互作用也被α - 甲基 - D - 甘露糖苷阻断，但不被α - 甲基 - D - 葡萄糖苷阻断。用过碘酸钠对该糖蛋白进行化学修饰消除了其与分离的1型菌毛或1型菌毛化大肠杆菌相互作用的能力。这些结果表明，60千道尔顿糖蛋白的碳水化合物部分作为口腔中1型菌毛的受体，我们推测这种相互作用可能导致大肠杆菌的凝集和早期清除，从而防止这些微生物在口咽黏膜和牙齿组织上定植。
