Recombination and Genetics in Chlamydia spp.

衣原体的重组和遗传学。

• 批准号: 7824424
• 负责人: DANIEL D ROCKEY
• 金额: $ 49.48万
• 依托单位: OREGON STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-26 至 2011-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7824424
• 关键词: Address; Affect; Animals; Antibiotic Resistance; Area; Bacteria; Basic Science; Bioinformatics; Biology; Chlamydia; Chlamydia trachomatis; Chlamydophila pneumoniae; Chromosome Mapping; Chromosomes; Chronic; Communities; DNA; Data; Development; Disease; Ectopic Pregnancy; Electroporation; Eye; Eye Infections; Eye diseases; Family suidae; Genes; Genetic; Genetic Materials; Genetic Recombination; Genetic Transformation; Genital system; Genome; Genomics; Genotype; Goals; Horizontal Gene Transfer; Human; In Vitro; Individual; Infection; Laboratories; Lead; Maps; Measurable; Mediating; Mucous Membrane; Ofloxacin; Organism; Patients; Pelvic Inflammatory Disease; Perception; Phenotype; Process; Publishing; Recombinants; Recording of previous events; Research; Research Personnel; Resistance; Resources; Respiratory System; Respiratory tract structure; Rifampin; Sequence Analysis; Side; System; Techniques; Technology; Testing; Tetracycline Resistance; Tetracyclines; Trachoma; Transcript; Translational Research; Universities; Vaccine Design; Vaccines; Vacuole; Washington; Work; base; candidate identification; cost; design; fighting; gene function; genome sequencing; homologous recombination; in vivo; knock-down; novel; pathogen; patient population; phosphorodiamidate morpholino oligomer; public health relevance; repository; research study; resistance mechanism; resistant strain; therapeutic target; tool; vaccine candidate; vector

DESCRIPTION (provided by applicant): This application addresses broad Challenge Area (15) Translational Science, and specific Challenge Topic, 15-AI-106: Translational research focused on high priority pathogens and basic research focused on resistance mechanisms. Infections by Chlamydia trachomatis and C. pneumoniae cause diseases of the genital tract, eye, and respiratory tract in humans, and complications from these infections lead to chronic problems including trachoma, pelvic inflammatory disease, ectopic pregnancy, and perhaps other conditions. Millions of people worldwide are affected by these conditions, for which there are no effective vaccines. Discovery of useful vaccines and perhaps novel therapies against infection is complicated by the lack of a practical genetic system. The overall goals of this project work toward the development of a practical genetic system, through an examination of the mechanism of horizontal gene transfer by chlamydiae. Recent experimentation in our and other laboratories demonstrates that chlamydiae are actively recombinogenic in vitro and, very likely, in vivo. We have determined that these organisms are capable of mobilizing any of three antibiotic resistance genes between different strains and species, and stably retaining this DNA in the absence of selection. This includes measurable and frequent in vitro transfer of a tetracycline resistance marker to C. trachomatis from the pig pathogen C. suis. The mechanism of this transfer is not yet known. The following aims are proposed to utilize our developing technologies and accumulating preliminary data to elucidate the mechanism of natural genetic exchange in chlamydiae, and to exploit these findings to develop a practical genetic system for these organisms. In Aim 1 we will explore the mechanisms of recombination in Chlamydia spp., using differently resistant chlamydial strains already available in the laboratory. Aim 2 will use a recombination strategy as a tool for the mapping of map genes involved with known phenotypes in C. trachomatis. The final Aim will explore possible avenues for developing a practical technique for introducing genes into C. trachomatis. A common set of research tools will be used for each Aim, and these are largely already developed in our research group. Completion of these interactive Aims will significantly affect perceptions of how Chlamydia spp. interact in vivo, and may provide a practical transformation techniques that we can make available to the research community. They will also examine possible mechanisms that may allow C. trachomatis to acquire or transfer resistance genes in patient populations. PUBLIC HEALTH RELEVANCE: Millions of humans suffer serious diseases of the eye or genital tract caused by Chlamydia trachomatis. The study of possible vaccine candidates or logical therapeutic targets is limited by the lack of a practical genetic system. Our laboratories have developed recombination technologies that allow a study of the mechanisms involved in chlamydial recombination. Elucidating the mechanism of recombination in the chlamydiae will facilitate a rational approach to chlamydial transformation, which is also described in this proposal. Development of a workable genetic system will be important as researchers explore vaccine strategies to fight these bacteria.

描述（由申请人提供）：本申请涉及广泛的挑战领域 (15) 转化科学，以及具体的挑战主题 15-AI-106：重点关注高优先级病原体的转化研究和重点关注耐药机制的基础研究。沙眼衣原体和肺炎衣原体感染会导致人类生殖道、眼睛和呼吸道疾病，这些感染引起的并发症会导致慢性问题，包括沙眼、盆腔炎、宫外孕以及可能的其他病症。全世界有数百万人受到这些疾病的影响，但目前还没有有效的疫苗。由于缺乏实用的遗传系统，有用的疫苗和可能的抗感染新疗法的发现变得复杂。该项目的总体目标是通过检查衣原体水平基因转移机制来开发实用的遗传系统。我们和其他实验室最近的实验表明，衣原体在体外并且很可能在体内具有积极的重组能力。我们已经确定，这些生物体能够在不同菌株和物种之间调动三种抗生素抗性基因中的任何一种，并在没有选择的情况下稳定保留这种 DNA。这包括可测量且频繁地体外将四环素抗性标记物从猪病原体猪衣原体转移至沙眼衣原体。这种转移的机制尚不清楚。提出以下目标，利用我们正在开发的技术和积累的初步数据来阐明衣原体自然遗传交换的机制，并利用这些发现为这些生物体开发实用的遗传系统。在目标 1 中，我们将使用实验室已有的不同抗性衣原体菌株来探索衣原体属的重组机制。目标 2 将使用重组策略作为工具来绘制与沙眼衣原体已知表型相关的图谱基因。最终目标将探索开发一种将基因引入沙眼衣原体的实用技术的可能途径。每个目标都将使用一套通用的研究工具，这些工具大部分已经在我们的研究小组中开发出来。完成这些互动目标将显着影响人们对衣原体属的看法。体内相互作用，并可能提供一种实用的转化技术，我们可以将其提供给研究界。他们还将研究沙眼衣原体在患者群体中获得或转移耐药基因的可能机制。 公共卫生相关性：数百万人患有由沙眼衣原体引起的严重眼部或生殖道疾病。由于缺乏实用的遗传系统，对可能的候选疫苗或逻辑治疗靶点的研究受到限制。我们的实验室已经开发了重组技术，可以研究衣原体重组的机制。阐明衣原体中的重组机制将有助于采取合理的衣原体转化方法，这也在本提案中进行了描述。随着研究人员探索对抗这些细菌的疫苗策略，开发可行的遗传系统将非常重要。