MICROBIAL ANTIGENS ASSOCIATED WITH SPECIFIC ADHERENCE

对放线菌菌毛的研究仍在继续 调节这些粘附性的粘附性粘菌和内氏拟青霉 口腔细菌到各种细胞和口腔组织表面，从而 有助于微生物定植、牙菌斑形成和 牙周炎和牙周病的发病。类型1 粘性支原体菌毛与细菌附着有关 后天唾液膜到牙齿。氨基酸序列 类型1菌毛亚基的类型现在已经从 克隆基因的核苷酸序列。某些抗1型抗体 菌毛抗体以前被证明可以阻断细菌 吸附在唾液处理的羟基磷灰石上；然而，抗体 针对59kD的菌毛亚基似乎很差 吸附抑制剂，即使它们与类型1反应 放线菌上的菌毛。因此，菌毛亚基可能不是 直接参与粘合剂的相互作用。2型猪瘟菌毛 维氏原虫和纳氏原虫与一种 Gal/GalNAc特异性凝集素活性。2型菌毛亚基 经克隆和鉴定为60kD蛋白。 相应基因在大肠杆菌中的表达。DNA- 通过DNA杂交观察到A. 纳氏杆菌和粘性弧菌2型菌毛亚基以及 内氏弧菌2型和粘性弧菌1型亚基。因此， 放线菌不同菌毛种类的研究。可由以下部分组成 由来自共同祖先的基因编码的亚基。这个 血链球菌34的2型放线菌菌毛受体HAS 经鉴定为一种线形多糖，由相同的 六糖单元通过磷酸二酯桥相连。 六糖的不同结构特征似乎是 由于凝集素的特异性参与了凝集素和抗体的识别 细菌共聚集与细菌共聚集有显著的不同。 抗多糖抗体。这些研究已经开始 为理解口语的特殊性提供了结构基础 微生物黏附与口腔细菌耐药机制 免疫系统。

Studies are continuing to define the fimbriae of Actinomyces viscosus and A. naeslundii that mediate the adherence of these oral bacteria to various cells and oral tissue surfaces and thereby contribute to microbial colonization, dental plaque formation and the initiation of gingivitis and periodontal disease. The type 1 fimbriae of A. viscosus are involved in bacterial attachment to the acquired salivary pellicle to teeth. The amino acid sequence of the type 1 fimbrial subunit has now been deduced from the nucleotide sequence of the cloned gene. Certain anti-type 1 fimbrial antibodies were previously shown to block bacterial adsorption to saliva-treated hydroxyapatite; however, antibodies directed against the 59 Kd fimbrial subunit appear to be poor inhibitors of adsorption even though they reacted with the type 1 fimbriae on actinomyces. Thus, the fimbrial subunit may not be directly involved in the adhesive interaction. Type 2 fimbriae of A. Viscosus and A. naeslundii have been associated with a Gal/GalNAc specific lectin activity. The type 2 fimbrial subunit of A. naeslundii was identified as a 60 kD protein by cloning and expression of the corresponding gene in Escherichia coli. DNA- DNA hybridization was observed between the genes for A. naeslundii and A. viscosus type 2 fimbrial subunits as well as those for A. naeslundii type 2 and A. viscosus type 1 subunits. Thus, the different fimbriae of Actinomyces sp. may be composed of subunits encoded by genes derived from a common ancestor. The receptor for type 2 Actinomyces fimbriae on S. sanguis 34 has been identified as a linear polysaccharide formed by identical hexasaccharide units linked through phosphodiester bridges. Different structural features of the hexasaccharide appear to be involved in lectin and antibody recognition since the specificity of bacterial coaggregation is strikingly different from that of antibody against the polysaccharide. These studies have begun to provide a structural basis for understanding the specificity of oral microbial adherence and mechanisms by which oral bacteria resist the immune system.