CELL-CELL INTERACTION BETWEEN ORAL ACTINOMYCETES AND OTHER ORAL BACTERIA

口腔放线菌和其他口腔细菌之间的细胞间相互作用

• 批准号: 3775631
• 负责人: P E KOLENBRANDER
• 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/3775631
• 关键词: Actinomycetales; Bacteroides gingivalis; adhesin; bacterial genetics; cell cell interaction; ecology; genetic strain; molecular cloning; molecular pathology; mutant; nucleic acid probes; nucleic acid sequence; open reading frames; oral bacteria; receptor binding; tooth surface; transposon /insertion element

The focus of our research program is to understand the role of coaggregation in bacterial accretion of early colonizing bacteria on a clean tooth surface. The primary colonizers include actinomyces and streptococci. Antiserum against the 34.8-kDa surface-adhesin, ScaA, from Streptococcus gordonii PK488 cross reacts with a similar size protein from all 14 streptococcal strains so far tested that coaggregate with Actinomyces naeslundii PK606. The sequence of the 6.125 kb clone that contains scaA revealed six open reading frames. The adhesin gene is located adjacent to two genes encoding an ATP-binding protein and a hydrophobic membrane protein. These three genes are homologous to a cassette of genes encoding binding-protein dependent transport systems in several other bacteria. ScaA is a lipoprotein which probably is anchored in the cell membrane while its adhesin binding site is exposed to the environment. Two other oral streptococci also have the same genetic organization of these genes, suggesting that the adhesin is a critical function for colonization of oral streptococci. A 100-kDa protein thought to mediate intrageneric coaggregation among streptococci is absent in several spontaneous mutants and one transposon-inactivated mutant of Streptococcus gordonii DL1. Two potential coaggregation-mediating adhesins from Actinomyces serovar WVA963 strain PK1259 have been identified. Binding of oral actinomyces to defined glycolipid molecules appears to follow the sema specificity exhibited by the actinomyces coaggregations with oral streptococci. The long range goal of these studies, collectively, is to elucidate the molecular mechanisms responsible for bacterial colonization in the human oral ecosystem.

我们研究计划的重点是了解 早期定殖菌在细菌生长过程中的共聚集 在干净的牙齿表面上。主要殖民者包括 放线菌和链球菌。34.8 kDa抗血清 戈登链球菌PK488株表面粘附素SCAA 与来自所有14种链球菌的相似大小的蛋白质反应 迄今已测试的菌株与奈斯伦迪放线菌共聚集 PK606。包含SCAA的6.125 kb克隆的序列 揭示了六个开放阅读框架。粘附素基因被定位 与编码ATP结合蛋白的两个基因和一个 疏水性膜蛋白。这三个基因是同源的 编码结合蛋白依赖运输的基因盒 其他几种细菌中的系统。SCAA是一种脂蛋白，它 可能是锚定在细胞膜上，而它的粘附素结合 网站暴露在环境中。另外两种口腔链球菌 也有相同的基因组织，这表明 粘附素是口腔定植的关键功能 链球菌。 一种被认为介导种内共聚集的100 kDa蛋白质 链球菌在几个自发突变株和一个突变株中缺失 戈登链球菌DL1转座子失活突变体。二 放线菌各血清型潜在共聚集介导的粘附素 已鉴定出WVA963菌株PK1259。口服液装订 放线菌对定义的糖脂分子似乎遵循 放线菌与SEMA共聚体表现出的SEMA特异性 口腔链球菌。这些研究的长期目标是， 总而言之，就是要阐明分子机制 细菌在人类口腔生态系统中的定植。