Iron Uptake and Virulence of Burkholderia pseudomallei

鼻疽伯克霍尔德菌的铁吸收和毒力

• 批准号: 6921328
• 负责人: JORGE H CROSA
• 金额: $ 30.2万
• 依托单位: OREGON HEALTH & SCIENCE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-07-15 至 2007-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6921328
• 关键词: Burkholderia; bacteria infection mechanism; bacterial cytopathogenic effect; bacterial disease; bacterial genetics; biological transport; bioterrorism /chemical warfare; chemical structure; chemical structure function; gene expression; gene targeting; high performance liquid chromatography; host organism interaction; intracellular; iron; iron metabolism; laboratory mouse; macrophage; mass spectrometry; microarray technology; mutant; nuclear magnetic resonance spectroscopy; septicemia; siderophores; virulence; zoonosis

DESCRIPTION (provided by applicant): Melioidosis and glanders are life threatening infectious diseases with similar patho-physiology caused respectively by the select agents Burkholderia pseudomallei and B. mallei, with dramatic repercussions in the field of bio-defense. Despite major recent advances including the elucidation of the entire genome sequence of B. pseudomallei K96243 and the ongoing sequencing of the B. mallei genome, little is known about their mechanisms of virulence. Our long-range goal is to elucidate the pathogenesis of these diseases. Although many factors can contribute to bacterial virulence, one important nonspecific mechanism of defense pathogenic bacteria must overcome to establish infection, is the ability of human and animal hosts to withhold iron. Thus, a competitive advantage for microorganisms is the possession of genetic determinants encoding products that allow them to utilize otherwise unavailable iron. The immediate goal of our research is to use a combination of genetic and biochemical approaches to unveil specific mechanisms of iron uptake employed by these pathogens during both the septicemic and the intracellular phases of disease. To accomplish these goals we will perform: 1. Microarray and mutational analysis. We will use microarray chips to examine the differential gene expression of B. pseudomallei K96243, from cells grown in vitro under conditions of iron repletion and limitation. We will also examine patterns of gene expression induced in B. pseudomallei during infection of macrophages. In conjunction with microarray analysis we will generate knock-out mutants of important iron uptake genes in B. pseudomallei, identified from the available genome sequencing project. Selected iron uptake mutants will be assessed for their subsequent ability to invade and survive intracellularly in macrophages and for virulence in animal models. 2. The characterization and structural analysis of siderophores from B. pseudomallei and B. mallei. We will characterize the structure of siderophores produced by wild type and mutant B. pseudomallei (K96243) and B. mallei (ATCC 23344). These compounds will be purified by high performance liquid chromatography and their structural details determined by nuclear magnetic resonance and mass spectrometry. Knowledge gained from our investigation will contribute to the development of measures to control the diseases caused by these pathogens.

描述（由申请方提供）：类鼻疽和鼻疽是分别由选择性病原体类鼻疽伯克霍尔德菌和B引起的具有相似病理生理学的危及生命的传染病。在生物防御领域产生了巨大的影响。尽管最近取得了重大进展，包括阐明了B的整个基因组序列。假鼻疽K96243和正在进行的B的测序。鼻疽基因组，很少有人知道他们的毒力机制。我们的长期目标是阐明这些疾病的发病机制。虽然许多因素可以导致细菌的毒力，但致病菌必须克服的一个重要的非特异性防御机制是人类和动物宿主抑制铁的能力。因此，微生物的一个竞争优势是拥有编码产品的遗传决定因素，使它们能够利用否则不可用的铁。我们研究的直接目标是使用遗传和生化方法的组合来揭示这些病原体在败血症和细胞内阶段疾病期间所采用的铁摄取的特定机制。为了实现这些目标，我们将执行：1。微阵列和突变分析。我们将使用微阵列芯片来检测B的差异基因表达。pseudomallei K96243，来自在铁补充和限制条件下体外生长的细胞。我们还将研究在B中诱导的基因表达模式。在巨噬细胞感染期间的假鼻疽。结合微阵列分析，我们将产生B中重要铁吸收基因的敲除突变体。从现有的基因组测序计划中鉴定的假鼻疽。将评估选定的铁摄取突变体随后在巨噬细胞中侵入和细胞内存活的能力以及在动物模型中的毒力。2. B铁载体的表征和结构分析。类鼻疽和B.鼻疽我们将描述由野生型和突变体B产生的铁载体的结构。pseudomallei（K96243）和B.鼻疽菌（ATCC 23344）。这些化合物将通过高效液相色谱法进行纯化，并通过核磁共振和质谱法确定其结构细节。从我们的调查中获得的知识将有助于制定控制这些病原体引起的疾病的措施。