Proteomics study of Bacteroides forsythus

描述：病原微生物通过表达称为毒力因子的特定基因产物而在宿主内存活并造成损害。尽管有新的证据表明，Bacteroides extracanthus（Bf）是一种重要的牙周病细菌，这种微生物启动和介导的致病过程的确切机制几乎是未知的，因为其毒力因子的信息有限。因此，为了进一步了解Bf感染，需要鉴定和表征Bf的未知毒力因子。 本申请的初步数据表明，比较双向凝胶电泳（2-DE）可用于检测Bf的差异表达蛋白，从而发现在体内选择性表达的蛋白。本申请的目的是使用蛋白质组学研究来鉴定和表征Bf的体内表达蛋白。预计这种新的方法，结合Bf基因组序列的分析，将导致检测，鉴定和表征Bf的潜在毒力因子。 为了实现这一目标，本研究提出了以下具体目标：1）利用双向电泳技术检测Bf的差异表达蛋白。通过2-DE技术比较体外培养和体内培养的Bf细胞的蛋白质谱，检测出在体内选择性表达的蛋白质; 2）利用质谱和数据库检索技术鉴定和表征差异表达的蛋白质。将通过质谱法确定体内表达的蛋白质的身份，并搜索Bf基因组和蛋白质数据库。这种方法将为产生新的假设提供基础，这些假设可以在未来的研究中进行测试，其中候选毒力因子的真实毒力功能可以得到验证。 从这些研究中获得的结果将有助于实现本实验室的长期目标：通过提供更多关于其毒力因子的信息，更好地了解Bf的致病性。

DESCRIPTION: Pathogenic microorganisms survive and cause damage within the host by expressing specific gene products called virulence factors. Despite emerging evidences indicating that Bacteroides forsythus (Bf) is a crucial periodontopathic bacterium, the exact mechanisms whereby this microorganism initiates and mediates the pathogenic process are virtually unknown because of the limited information on its virulence factors. Therefore, in order to advance understanding of Bf infection, it is required to identify and characterize unknown virulence factors of Bf. Preliminary data presented in this application indicated that comparative 2-dimensional gel electrophoresis (2-DE) could be used to detect differentially expressed proteins of Bf, and the proteins selectively expressed in vivo were thus discovered. The purpose of this application is to identify and characterize in vivo-expressed proteins of Bf using proteomics study. It is expected that this novel approach, combined with the analysis of the Bf genome sequence, will lead to detection, identification, and characterization of potential virulence factors of Bf. In order to achieve this goal, the following Specific Aims are proposed: 1) to detect differentially expressed proteins of Bf by 2-DE. By comparing the protein profiles of in vitro- and in vivo-grown Bf cells using 2-DE, the proteins selectively expressed in vivo will be detected; 2) to Identify and characterize differentially expressed proteins using mass spectrometry and database search. Identity of in vivo-expressed proteins will be determined by mass spectrometry and search for Bf genome and protein database. This approach will provide a foundation for generating novel hypotheses that can be tested in future studies, in which authentic virulence function of the candidate virulence factors can be validated. The results obtained from these studies will assist to achieve a long-term goal of this laboratory: to gain a better understanding of the pathgogenic of Bf by providing more information on its virulence factors.