Functional genomics for Chlamydia

项目摘要/摘要 对于细菌病原体，第一批开始定义微生物功能遗传性质的研究 全基因组的规模，往往代表着一项里程碑式的、极具影响力的成就。最重要的人类 病原体沙眼衣原体是一种在很大程度上没有进行过此类研究的细菌 由于衣原体专属的细胞内性质和历史上对现代遗传扰动的顽固性。 随着我们团队开发了两种主要的衣原体基因工具-转座子诱变和 条件性温度敏感突变体--衣原体的功能基因组研究现已成为可能。 我们的长期目标是在全球范围内定义和功能描述与 沙眼衣原体感染及其发病机制。使用上述新方法，我们建议： (I)在模型中建立转座子和温度敏感条件突变体的已定义突变体文库 衣原体菌株，(Ii)筛选这些文库在体外和体内生长缺陷的标志，使用临床 相关的小鼠生殖道模型，以及(Iii)确定与宿主适应相关的衣原体基因 通过利用衣原体的种间横向基因转移和人类亲本株无法 感染老鼠。 这些努力对于从功能上了解衣原体基因在人体内的作用至关重要。 生物体的生长发育，以及衣原体的进化适应，成功维持 复杂哺乳动物宿主的感染和发病机制。我们预计衣原体将成为一个典范 专性胞内细菌，因此，从这项工作中获得的知识将广泛扩展到 其他类似地在哺乳动物宿主中进化出专有细胞内生态位的病原体。 识别这些基因座对于我们理解衣原体适应的机制是至关重要的。 哺乳动物宿主，这是朝着阐明主要毒力相关的重要一步。 人类体内的沙眼衣原体。

PROJECT SUMMARY/ABSTRACT For bacterial pathogens, the first studies that begin to define the microorganism’s functional genetic nature on a genome-wide scale, frequently represent a landmark and highly impactful achievement. The major human pathogen, Chlamydia trachomatis, is a bacterium for which such studies have not been performed, in large part due to Chlamydia’s obligate intracellular nature and historical intractability to modern genetic perturbations. With the development of two major genetic tools for Chlamydia by our group—transposon mutagenesis and conditional temperature-sensitive mutants—functional genomic investigations in Chlamydia are now possible. Our long term goal is to globally define and functionally characterize the genetic correlates to C. trachomatis infection and pathogenesis. Using the new approaches described above, we propose to: (i) build defined mutant libraries of transposon and temperature-sensitive conditional mutants in model Chlamydia strains, (ii) screen these libraries for hallmark in vitro and in vivo growth defects using a clinically relevant murine genital tract model, and (iii) determine the Chlamydia genes associated with host adaptation by exploiting interspecies lateral gene transfer for Chlamydia and the inability of human parental strains to infect mice. These efforts are essential for gaining a functional appreciation of the role chlamydial genes play in the organism’s growth and development, and also Chlamydia’s evolutionary adaptation to successfully maintain infection and pathogenesis in complex mammalian hosts. We anticipate that Chlamydia will serve as a model obligate intracellular bacterium, and, therefore, the knowledge obtained from this work will broadly extend to other pathogens that have similarly evolved an obligate intracellular niche in their mammalian hosts. Identification of these loci is critical for our understanding the mechanism of Chlamydia adaptation to mammalian hosts, and is an important step towards elucidating the major virulence correlates of C. trachomatis in humans.