Molecular Basis of Interspecies Recognition and Interaction

描述（由申请人提供）：我们目前对细菌生命各方面的了解，无论是代谢活性还是发病机制，大多是通过研究单种培养物中的细菌获得的。然而，在自然界中，细菌几乎总是存在于多物种群落中。其他菌种的存在如何影响特定细菌的代谢活性或致病能力，不仅对基础研究微生物学家，而且对临床微生物学家都是一个重要的问题。已经确定的是，人体上的固有微生物区系在人类宿主的健康和疾病中发挥重要作用。例如，一些最普遍的传染病如龋齿、牙周病、阴道炎和炎性肠综合征被认为是由固有微生物群落组成的变化引起的。因此，了解不同物种如何在多物种社区中相互作用，有助于制定适当的控制措施，以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，作为一种模式生物和牙菌斑作为一个模型系统，以了解在多物种微生物群落的种间相互作用。提出了两个具体目标：目标1。利用基因芯片技术寻找S.变异体对物种间相互作用的反应。目标二。利用随机诱变方法鉴定和表征调控S.变种到其他物种。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.