Molecular Genetic Analysis of Chlamydia Pathogenicity

描述(申请人提供)：衣原体属细菌是动物和人类的重要病原体。衣原体引起的疾病。男性包括肺炎、心内膜炎、多发性关节炎、失明和广泛的性传播疾病，女性包括宫颈、输卵管炎、盆腔炎和不孕症；男性包括非淋菌性尿道炎和急性附睾炎。衣原体也被认为是各种慢性疾病的辅助因素，如冠心病。尽管多年来的努力，衣原体仍然难以进行遗传分析，因为他们专属的细胞内生活方式和复杂的发育周期。还没有人能够将外源DNA导入这个生物体，并实现外源基因的稳定遗传和表达。我们的长期目标是应用遗传学的力量来研究衣原体的致病机制。这一建议的目的包括开发用于分析衣原体发病机制的遗传工具，以及以假设为驱动的目的，以解决衣原体生物学的具体问题。其具体目的是：1)建立外源DNA在衣原体中的导入、表达和稳定维持的方法以及衣原体中的基因替换系统；2)确定衣原体合成肽聚糖的途径；3)确定衣原体生长所必需成分的运输系统，特别是甲基转移酶甲基供体的来源。我们将使用遗传、生化和细胞生物学策略来实现每个目标。成功实现第一个目标将对衣原体研究产生重大影响，因为它将使衣原体基因分析的新工具可用。这些新技术将使我们在了解衣原体的发病机制和生物学以及构建衣原体突变株用于疫苗开发的能力方面取得快速进展。目标2的成功将最终解决衣原体异常，而目标3将试图解决衣原体生物学的另一个明显的悖论。因此，这两个目标将解决衣原体生物学的一些长期存在的问题，并扩大我们对这种重要病原体细胞内生活方式的了解。

DESCRIPTION (provided by applicant): Bacteria of the genus Chlamydia are significant pathogens of animals and man. The diseases caused by Chlamydia spp. in man include pneumonia, endocarditis, polyarthritis, blindness, and a wide range of sexually transmitted diseases including cervicitis, salpingitis, pelvic inflammatory disease, and infertility in females; and non-gonococcal urethritis and acute epididymitis in males. Chlamydia has also been implicated as a cofactor in a variety of chronic diseases such as coronary heart disease. Despite many years of effort, the Chlamydia remain intractable to genetic analysis due to their obligate intracellular lifestyle and complex developmental cycle. No one has been able to introduce foreign DNA into this organism and achieve stable inheritance of and expression of the foreign genes. Our long-term goal is to apply the power of genetics to study the pathogenic mechanisms of Chlamydia. The aims of this proposal include the development of genetic tools for the analysis of Chlamydia pathogenesis and hypothesis-driven aims to address specific questions of Chlamydia biology. The specific aims are to: 1) develop a method for introduction, expression, and stable maintenance of foreign DNA in Chlamydia and a system for gene replacement in Chlamydia; 2) characterize the pathway for peptidoglycan synthesis in Chlamydia; and, 3) identify the transport system for uptake of essential constituents for Chlamydia growth, specifically the source of methyl donors for methyltransferases. We will employ genetic, biochemical and cell biology strategies to each aim. Success in achieving the first aim will have a significant impact on Chlamydia research by making new tools for genetic analysis of Chlamydia available. Rapid advances in our understanding of Chlamydia pathogenesis and biology as well as the ability to construct Chlamydia mutants for vaccine development will be made possible by these new techniques. Success in aim 2 will finally resolve the Chlamydia anomaly while aim 3 will attempt to resolve another apparent paradox of Chlamydia biology. Thus, these two aims will resolve some long-standing questions of Chlamydia biology and extend our knowledge of the intracellular lifestyle of this important pathogen.