Pseudomonas aeruginasa LPS: A Post-Genomic Analysis

描述（由申请方提供）：本研究的长期目标是了解脂多糖（LPS）在铜绿假单胞菌毒力中的作用，以开发新的治疗方法和疫苗来对抗这种重要的病原体。铜绿假单胞菌LPS的O抗原部分是急性感染中的毒力所需的，并且其丧失对于囊性纤维化患者的慢性肺部感染至关重要。在父母补助金的实验是针对定义的O抗原从血清群O 11菌株PA 103的合成途径，确定该O抗原基因座的转录组织，并测试O抗原突变体在两个不同的小鼠感染模型。这项探索性资助的目的是了解铜绿假单胞菌0抗原是如何调节的。已显示显著影响铜绿假单胞菌0抗原表达的条件之一是温度;在45 ° C下，没有0抗原表达。我们将分析RNA和蛋白质产物，以确定O抗原是否是转录或转录后调节。使用遗传学方法，我们将确定O抗原调节器。我们将突变这种温度调节器，并使用后基因组技术，包括微阵列和蛋白质组学分析，以确定其他基因和蛋白质的调节与O抗原。揭示这种调节的性质将使我们能够提出抑制O抗原表达的机制，从而降低这种细菌在急性感染中的毒力。通过该资助获得的结果，结合母提案中描述的突变分析和毒力研究，可能有助于开发针对这种重要机会致病菌的新策略。

DESCRIPTION (provided by the applicant): The long-term goal of this research is to understand the role of lipopolysaccharide (LPS) in the virulence of Pseudomonas aeruginosa in order to develop novel therapeutics and vaccines to combat this important pathogen. The O antigen portion of P. aeruginosa LPS is required for virulence in acute infections and its loss is critical for chronic lung infections in cystic fibrosis patients. The experiments in the parent grant are directed at defining the pathway of synthesis of the O antigen from the serogroup O11 strain PAl03, determining the transcriptional organization of this O antigen locus, and testing O antigen mutants in two different mouse models of infection. The goal of this exploratory grant is to understand how P. aeruginosa 0 antigen is regulated. One of the conditions that has been shown to dramatically effect the expression of P. aeruginosa 0 antigen is temperature; at 45 degrees C, no O antigen is expressed. We will analyze RNA and protein products to determine whether O antigen is transcriptionally or post-transcriptionally regulated. Using genetic approaches, we will identify the O antigen regulator. We will mutate this temperature regulator and use post-genomic techniques including micro-array and proteomic analyses to identify additional genes and proteins that are regulated with O antigen. Uncovering the nature of this regulation will allow us to propose mechanisms to inhibit O antigen expression and thereby decrease the virulence of this bacterium in acute infections. Results obtained through this grant, in combination with the mutational analysis and virulence studies described in the parent proposal, may be beneficial in the development of new strategies that target this important opportunistic pathogen.