The role of disulfide bonding in type III secretion of Chlamydia spp.

描述（由申请人提供）：衣原体属包含代表美国重大健康问题的成员。由于急性和慢性疾病的流行及其对健康和社会经济的综合影响，造成了重大负担。衣原体是专性细胞内寄生虫，经历复杂的发育周期，伴随着基因表达，形态和蛋白质功能的明显改变。例如，毒性相关III型分泌系统（T3SS）的表达和活性与发育进程密切相关。此外，二硫键动力学的外被膜的衣原体属。在发育周期中起着主导作用，但尚未完全理解。我们有初步证据表明T3 S蛋白参与了二硫键发育相关的改变。我们提出了一种组合的方法，旨在表征T3S装置蛋白之间的二硫键，以建立的程度，时间动态，和分泌活性的影响。大量的重点已经放在分泌的效应蛋白的识别和表征，而相对较少的是已知的T3S装置衣原体生物学的更直接的贡献。尽管T3S过程在革兰氏阴性病原体中显示出显著的功能保守性，但衣原体定植的高度独特的生态位可能导致衣原体系统的新机制。因此，这些研究将为T3S机制的知识增加一个新的维度，提高对衣原体介导的疾病的理解，并可能产生新的预防和治疗方法。 公共卫生相关性：衣原体属包含重要的人类病原体。这些细菌具有复杂的双相发育周期，并表达抗宿主蛋白发育所必需的III型分泌系统。该提案包含旨在探索分泌系统的发育周期和活动之间的联系的工作。

DESCRIPTION (provided by applicant): The Chlamydia genus contains members representing significant health concerns in the United States. A significant burden exists due to prevalence and the combined health and socioeconomic impact of acute and chronic disease. Chlamydiae are obligate intracellular parasites that undergo a complex developmental cycle that is accompanied by distinct alterations in gene expression, morphology, and protein function. For example, expression and activity of the virulence-associated type III secretion system (T3SS) is intimately coupled to developmental progression. In addition, disulfide bond dynamics in the outer envelope of Chlamydia spp. has a dominant, yet incompletely understood, role in the developmental cycle. We have preliminary evidence that T3S proteins participate in developmentally associated alterations in disulfide bonding. We propose a combination of methods designed to characterize disulfide bonding among T3S apparatus proteins to establish the extent, temporal dynamics, and impact on secretion activity. A great deal of emphasis has been placed on identification and characterization of secreted effector proteins while comparatively little is known regarding more direct contributions of the T3S apparatus to chlamydial biology. Although the T3S process displays a significant degree of functional conservation among Gram-negative pathogens, it is likely that the highly unique niche colonized by chlamydiae results in mechanisms novel to the chlamydial system. Therefore, these studies will add a new dimension to knowledge regarding the T3S mechanism, lead to an enhanced understanding of Chlamydia-mediated disease, and potentially yield novel preventative and treatment therapies. PUBLIC HEALTH RELEVANCE: The Chlamydia genus contains species that are important human pathogens. These bacteria have a complex, biphasic developmental cycle and express a type III secretion system essential of development of the anti-host proteins. This proposal contains work designed to explore the link between the developmental cycle and activity of the secretion system.