MICROBIAL ANTIGENS ASSOCIATED WITH SPECIFIC ADHERENCE

粘性放线菌T14 V 1型和放线菌的亚基 已通过克隆鉴定了naeslundii WVU 45 2型菌毛 以及各基因在大肠杆菌中的表达。 的 从核苷酸序列推导出每个亚基的氨基酸序列 克隆基因的序列和N-末端序列证实 通过Edman降解纯化的菌毛和克隆的菌毛 亚单位 1型和2型菌毛亚单位的基因编码 约530个氨基酸残基的蛋白质， 前30到32看起来是信号序列。 一个进化 放线菌亚基之间的关系。1型和 2型菌毛从氨基酸序列同源性是明显的。 用A.粘病毒T14 V和突变体 特别是缺乏1型、2型或两种类型的菌毛， 提供了证据表明，酸性脯氨酸丰富的蛋白质是 菌毛型的特异性受体。 这些唾液成分 未被糖基化，因此，它们被A.粘性 1型菌毛最可能依赖于蛋白质-蛋白质 交互. 相反，链球菌上的受体分子 sanguis 34为放线菌属。2型菌毛为线状 由磷酸二酯连接的六糖组成的多糖 亚单位。 兔抗体与该多糖的反应 取决于六糖链的非还原端， GalNAc β 1导致3Gal在还原端参与凝集素 识别. 抗原决定簇的类似分离， 受体结构存在于S.血竭 J22 然而，对于菌株J22，Gal β 1导致3GalNAc， 寡糖亚基的还原端似乎参与了 在凝集素识别中。 因此，这些受体的活性 链球菌多糖可能依赖于内部结构 模拟糖蛋白和糖脂受体的功能， 宿主细胞

The subunits of Actinomyces viscosus T14V type 1 and Actinomyces naeslundii WVU45 type 2 fimbriae have been identified by cloning and expression of the respective genes in EScherichia coli. The amino acid sequence of each subunit was deduced from the nucleotide sequence of the cloned gene and the N-terminal sequence confirmed by Edman degradation of purified fimbriae and cloned fimbrial subunit. The genes for type 1 and type 2 fimbrial subunits encode proteins of approximately 530 amino acid residues of which the first 30 to 32 appear to be signal sequences. An evolutionary relationship between the subunits of Actinomyces spp. type 1 and type 2 fimbriae was evident from amino acid sequence homologies. Studies of bacterial adherence using A. viscosus T14V and mutants specifically lacking type 1, type 2 or both types of fimbriae have provided evidence that the acidic proline rich proteins are specific receptors for type fimbriae. These salivary components are not glycosylated and thus, their recognition by A. viscosus type 1 fimbriae most likely depends on protein-protein interactions. In contrast, the receptor molecule on Streptococcus sanguis 34 for Actinomyces spp. type 2 fimbriae is a linear polysaccharide composed of phosphodiester-linked hexasaccharide subunits. The reaction of rabbit antibody with this polysaccharide depends on the nonreducing end of the hexasaccharide chain while GalNAc beta 1 leads 3Gal at the reducing end is involved in lectin recognition. A similar separation of the antigenic determinant and receptor structure occurs within the polysaccharide of S. sanguis J22. However, with strain J22, Gal beta 1 leads to 3GalNAc at the reducing end of the oligosaccharide subunit appears to be involved in lectin recognition. Thus, the receptor activity of these streptococcal polysaccharides may depend on internal structural features that mimic the glycoprotein and glycolipid receptors on host cells.