Functional Characterization of Essential Burkholderia pseudomallei Virulence Regulators

 描述(由申请人提供)：假鼻疽伯克霍尔德氏菌(BP)是一种兼性细胞内病原体，由于其潜在的生物武器用途及其引起的致命疾病类鼻疽病，是一种一级选择剂。类鼻疽病有各种各样的症状，基本上影响到身体的每一个组织。临床表现的差异是由于BP在不同物种之间的遗传多样性，以及具有广泛的毒力机制来建立疾病，为了开发有效的疫苗和治疗策略，BP的分子发病机制必须被阐明。到目前为止，只有少数几种致病机制被描述，对于一种具有非常大和多样化的7兆碱基对的基因组的细菌。通过我们的创新方法，在感染的不同阶段转录描述单个BP细胞，我们已经确定了四个假想的调节因子，对于完整的BP在体内的发病是必不可少的。为了研究致病过程和受这些调控因子控制的基因，我们提出了目标1，它将识别调控网络并表征它们在发病中的作用。这将有助于阐明已知的毒力途径和/或新的毒力途径的调控，增加对BP细胞内生命周期的完整理解。Aim 2通过确定整个基因组中DNA-调控因子的相互作用，提出了这些新的转录调控因子的机制特征。这一分析将允许识别每个调节子的结合基序，并验证其 功能。综上所述，提出的目标将极大地丰富对宿主内BP感染的了解，从而有助于开发新的疫苗和治疗策略。这项建议中使用的总体方法学对研究其他具有医学意义的兼性细胞内病原体具有广泛的适用性。

 DESCRIPTION (provided by applicant): Burkholderia pseudomallei (Bp), a facultative intracellular pathogen, is a tier 1 select agent due to its potential use as a bioweapon and the often fatal disease it causes, melioidosis. Melioidosis has a wide variety of symptoms that affects essentially every tissue of the body. The varieties in clinical manifestations is due to th fact that Bp is genetically diverse among species and has a wide array of virulence mechanisms used to establish disease In order to develop effective vaccines and treatment strategies, the molecular pathogenesis of Bp must be elucidated. To date, only a handful of pathogenesis mechanisms have been described, for a bacterium with a very large and diverse genome of >7 mega base pairs. Through our innovative approach of transcriptionally profiling single Bp cells at different stages of infection, we have identified four hypothetical regulators essential for complete Bp pathogenesis in vivo. To study the pathogenic processes and the genes controlled by these regulators we propose Aim 1, which will identify the regulation networks and characterize their roles in pathogenesis. This will shed light on the regulation of either known virulence pathways and/or novel virulence pathways adding to the complete understanding of the Bp intracellular lifecycle. Aim 2 proposes the mechanistic characterization of these novel transcriptional regulators by determining DNA- regulator interactions across the entire genome. This analysis will allow for identification of binding motifs for each regulator and validate their function. Taken together, the proposed aims will greatly enrich the understanding of Bp infection within the host that can lead to the development of novel vaccine and therapeutic strategies. The overall methodology used in this proposal has broad applicability to study other medically significant facultative intracellular pathogens.