MICROBIAL ANTIGENS ASSOCIATED WITH SPECIFIC ADHERENCE

与特异性粘附相关的微生物抗原

• 批准号: 3753492
• 负责人: J O CISAR
• 金额: --
• 依托单位: NATIONAL INSTITUTE OF DENTAL & CRANIOFACIAL RESEARCH
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/3753492
• 关键词: Actinomyces; Streptococcus; Streptococcus mitis; Streptococcus sanguis; bacterial antigens; bacterial polysaccharides; bacterial proteins; cell adhesion; dental caries; dental plaque; ecology; gene expression; genetic strain; gram negative bacteria; hydroxyapatites; lectin; microorganism interaction; molecular pathology; oral bacteria; receptor binding; receptor expression; saliva; surface antigens

Structural studies showed that the Streptococcus gordonii 38 receptor polysaccharide was composed of a repeating heptasaccharide linked end to end by phosphodiester bonds. The heptasaccharide repeating units of strain 38 and S. mitis J22 differed only at their reducing ends with GalNAcbeta13Gal in the former and Gal- beta13GalNAc in the latter while a rhamnose branch near the nonreducing end of the strain 38 heptasaccharide distinguished this structure from the linear hexasaccharide of S. oralis 34. Certain strains of S. sanguis and S. gordonii that express GalNAc-sensitive lectins coaggregated with strains 38 and 34 which have GalNAc- beta(13)Gal-containing receptor polysacchides but not with S. mitis J22 which has a Gal-beta13GalNAc containing receptor polysaccharide. Presumably, the complimentarity of these lectins involves the side of GalNAc-beta13Gal that includes the acetamido group of GalNAc-beta. In contrast, actinomyces interact with both types of receptor polysaccharides which suggests lectin complimentarity for a side of GalNAc-beta13Gal that is shared with Gal-beta13GalNAc. The antigenic properties of these polysaccharides appear to depend on structural features distinct from those detected by lectin binding. For example, the presence of the common rhamnose branch accounts for the strong cross reactivity between the strain 38 and J22 polysaccharides. A structural understanding of these cross reactions provides a rational basis for the preparation of specific immunological reagents. Studies were also initiated to characterize the adhesive properties of viridans streptococci that colonize the human oral cavity shortly following birth and also following the eruption of teeth. Whereas isolates obtained during the first two months were relatively nonadherent, isolates obtained after tooth eruption exhibited an array of adhesive properties similar to those noted in studies of adult isolates. The results clearly implicate specific bacterial adhesive properties as important determinants of in vivo colonization.

结构研究表明，戈登链球菌 38 受体多糖由重复的七糖组成 通过磷酸二酯键首尾相连。 七糖 菌株 38 和 S. mitis J22 的重复单位仅在 它们的还原端为 GalNAcbeta13Gal 前者，Gal- beta13GalNAc 位于后者，而鼠李糖分支靠近 菌株 38 七糖的非还原端区分了这一点 来自 S.oralis 34 的直链六糖的结构。某些 表达 GalNAc 敏感的 S. sanguis 和 S. gordonii 菌株 凝集素与具有 GalNAc- 的菌株 38 和 34 共聚集 含 beta(13)Gal 的受体多糖，但不包括 S. mitis J22 具有含有 Gal-beta13GalNAc 的受体 多糖。 据推测，这些凝集素的互补性 涉及 GalNAc-beta13Gal 包含乙酰胺基的一侧 GalNAc-beta 组。 相反，放线菌与两者相互作用 表明凝集素的受体多糖类型 与 GalNAc-beta13Gal 的一侧互补 Gal-beta13GalNAc。 这些物质的抗原特性 多糖似乎取决于不同的结构特征 来自通过凝集素结合检测到的那些。 例如，存在 共同鼠李糖分支的强交叉 菌株38和J22多糖之间的反应性。 一个 对这些交叉反应的结构理解提供了 特异性免疫学制备的合理依据 试剂。 还开始研究粘合剂的特性 定植于人类口腔的草绿色链球菌的特性 出生后不久以及在萌出后不久出现的空洞 牙齿。而前两个月获得的分离株 相对不粘附，在牙齿萌出后获得的分离物 表现出一系列类似于中所述的粘合性能 成人分离株的研究。 结果清楚地暗示了具体的 细菌粘附特性是体内重要的决定因素 殖民化。