INHIBITION OF HUMAN CARIOGENIC STREPTOCOCCI

使用充分表征的凝集性单克隆抗体， 对各种表面成分，非凝集突变体的 将分离变形链球菌GS-5。 其中将有变种人 在包括血清型C抗原在内的一系列表面成分中有缺陷， 脂磷壁酸、葡糖基转移酶和其它表面抗原。 在 此外，将尝试分离GS-5微生物， 乳酸脱氢酶 来自现有基因库的质粒 （E.大肠杆菌和组成的GS-5 DNA插入到嵌合 能在E.大肠杆菌和链球菌）将被使用 将每个缺陷型GS-5突变体转化为正常的表面功能。 的 补充功能将被检测，丰富和选择， 使用先前提到的单克隆抗体进行凝集。 一个 替代方案，使用转座子失活产生两种突变体 和克隆的回复突变体，并被认为特别适用于 乳酸菌缺乏的微生物的分离。 该项目 旨在提供良好的特点，真正的等同性对GS-5 衍生物在各种属性上有缺陷，被认为与 致龋性 体外毒力试验将包括以下研究： 疏水组分之间的相互作用，凝集素-配体相互作用， 形成粘附性多糖和细菌-细菌 交互. 我们还计划与其他机构建立合作研究， 这些同基因对的体内动物研究的研究者。

Using well characterized, agglutinating, monoclonal antibodies directed against various surface constituents, non-agglutinating mutants of Streptococcus mutans GS-5 will be isolated. Among these will be mutants defective in a range of surface constituents including serotype c antigen, lipoteichoic acid, glucosyl transferase(s), and other surface antigens. In addition, attempts will be made to isolate GS-5 organisms defective in lactic dehydrogenase. Plasmids from an already available gene bank (generated in E. coli and consisting of GS-5 DNA inserts into a chimeric plasmid capable of replication in E. coli and in Streptococci) will be used to transform each deficient GS-5 mutant to normal surface function. The complemented function will be detected, enriched and selected by agglutination using the previously mentioned monoclonal antibodies. An alternate protocol, using transposon inactivation to generate both mutants and cloned revertants, is provided and is considered especially useful for the isolation of lactic dehydrogenese deficient organisms. The project is designed to provide well characterized, truly isogneic pairs of GS-5 derivatives defective in various properties thought to be associated with cariogenicity. In vitro assays for virulence will include studies of interactions between hydrophobic constitutents, lectin-ligand interactions, formation of adhesive polysaccharides, and bacterial-bacterial interactions. We also plan to establish collaborative studies with other investigators for in vivo animal studies of these isogenic pairs.