Molecular Basis of Interspecies Recognition and Interaction

描述（由申请人提供）：我们目前对细菌生命的各个方面的了解，无论是代谢活动还是发病机制，大多是通过研究单种培养的细菌获得的。然而，在自然界中，细菌几乎总是以多物种群落的形式存在。其他物种的存在如何影响特定细菌的代谢活动或致病能力不仅是基础研究微生物学家的重要问题，也是临床微生物学家的重要问题。人体上的本地微生物群在人类宿主的健康和疾病中起着重要的作用，这一点已经得到了充分的证实。例如，一些最流行的传染病，如龋齿、牙周病、阴道炎和炎症性肠综合征，被认为是由本地微生物群组成的变化引起的。因此，了解不同物种如何在多物种群落中相互作用有助于设计适当的控制措施来遏制这些多微生物疾病。在这项资助中，我们建议使用龋齿病原体变形链球菌作为模型生物，牙菌斑作为模型系统来了解多物种微生物群落中的物种间相互作用。提出了两个具体目标：目标1。利用微阵列技术寻找对种间相互作用有反应的变异链球菌的基因。目标2。利用随机诱变方法鉴定和表征调节突变链球菌对其他物种反应的基因。将使用各种最先进的分析工具来实现这些目标。

DESCRIPTION (provided by applicant): Our current knowledge of aspects of bacterial life, be it metabolic activities or pathogenesis, is mostly obtained by studying bacteria in monospecies cultures. Nevertheless, in nature bacteria almost always exist in multispecies communities. How the presence of other species affects the metabolic activity or the pathogenic capacity of a particular bacterium is an important question not only to basic research microbiologists, but also to clinical microbiologists. It has been well established that the indigenous microflora on the human body play an important role in the health and disease of the human host. For example, some of the most prevalent infectious diseases such as Dental caries, periodontal diseases, vaginitis, and inflammatory bowel syndrome are believed to be caused by a shift of the indigenous microflora composition. Therefore, understanding how different species interact in a multispecies community could help devise appropriate control measures to curb these polymicrobial diseases. In this grant, we propose to use the Dental caries pathogen, Streptococcus mutans, as a model organism and the Dental plaque as a model system to understand inter-species interactions in a multispecies microbial community. Two Specific Aims are proposed: Aim 1. Using microarray to hunt for the genes of S. mutans responding to interspecies interactions. Aim 2. Using a random mutagenesis approach to identify and characterize genes regulating the response of S. mutans to other species. A variety of state-of-the-art analytical tools will be used to achieve these Aims.