HEMIN RECEPTOR GENE FAMILY OF BARTONELLA QUINTANA

金塔纳巴尔通体的血红素受体基因家族

• 批准号: 7715619
• 负责人: Michael F Minnick
• 金额: $ 12.67万
• 依托单位: UNIVERSITY OF CALIFORNIA AT DAVIS
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-05-01 至 2009-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7715619
• 关键词: Acquired Immunodeficiency Syndrome; Arthropod Vectors; Bacillary Angiomatosis; Bacteremia; Bacteria; Bartonella; Bartonella Infections; Bartonella quintana; Biochemical Genetics; Boxing; Cardiovascular system; Cat-Scratch Disease; Complement; Computer Retrieval of Information on Scientific Projects Database; DNA Footprint; Data; Electrophoretic Mobility Shift Assay; Endocarditis; Erythrocytes; Funding; Gene Family; Genes; Goals; Gram-Negative Bacteria; Grant; Growth; Growth Factor; Hemin; Homelessness; Homologous Gene; Human; Infection; Infectious Agent; Institution; Lice; Life; Macaca; Maps; Membrane Proteins; Modeling; Molecular; Multigene Family; Neuroretinitis; Oroya Fever; Pathogenesis; Patients; Pattern; Peliosis Hepatis; Primates; Process; Protein Family; Proteins; Range; Receptor Gene; Regulation; Relapse; Research; Research Personnel; Resources; Reverse Transcriptase Polymerase Chain Reaction; Role; Source; Structure; Study models; Testing; Transcription Initiation Site; Trench Fever; United States National Institutes of Health; Vascular Endothelial Cell; angiogenesis; base; inner city; member; mutant; receptor; response; uptake; vector

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Objective: Five Bartonella species are emerging infectious agents responsible for Oroya fever, cat-scratch disease, bacillary angiomatosis, and trench fever in humans. Life-threatening complications of bartonellosis can include endocarditis, peliosis hepatis, relapsing bacteremia, encephelopathy and neuroretinitis. Bartonella quintana, the model for this study, is currently re-emerging in inner-city homeless people and in patients suffering from AIDS. Like all Bartonella, B. quintana colonizes the circulatory system, where it infects human erythrocytes, vascular endothelial cells, triggers angiogenesis and causes persistent bacteremia. Despite these remarkable attributes, little is known about the molecular pathogenesis of Bartonella. Because hemin is an essential growth factor for all Bartonella species and B. quintana has the greatest hemin requirement known for any bacterium, the long range goal of this study is to examine the molecular basis for hemin acquisition-- a process that would contribute not only to establishment of infection but persistence in the arthropod vector and human host. To this end, the proposal focuses on analysis of a five-gene family encoding B. quintana's major hemin receptor and four homologues. Specific Aim 1 will quantify hbp expression in response to varying hemin concentration using RT-PCR. We will also analyze the potential ferric uptake regulator (fur) box using electrophoretic mobility shift assays and DNA footprinting, and we will map hbp transcription initiation sites. We will also verify Fur's role in hbp regulation by quantifying hbp expression in both fur mutant and over-expressed fur backgrounds. In Specific Aim 2 the expression patterns of the hbp multigene family over the course of infection in the human louse vector and a macaque primate model will be analyzed. In addition, a mutant form of the dominant hbp gene and a trans-complemented strain will be generated to test molecular Koch's postulates in the primate model. In Specific Aim 3, we will determine the structure and function of the Hbp proteins by mapping functional receptor domains using biochemical and genetic approaches. In addition, we will determine whether Hbp's can transport hemin and will identify domains that are necessary for this function. These data will provide valuable information on a multigene family involved in an essential process for Bartonella growth and persistence. Further, since Bartonella Hbp's are possibly members of an outer membrane protein family from several Gram-negative bacteria, data generated from this study will undoubtedly be of broad importance to bacterial pathogenesis.

该副本是利用众多研究子项目之一 由NIH/NCRR资助的中心赠款提供的资源。子弹和 调查员（PI）可能已经从其他NIH来源获得了主要资金， 因此可以在其他清晰的条目中代表。列出的机构是 对于中心，这不一定是调查员的机构。 目的：五种Bartonella物种是负责Oroya发烧，猫抓病，杆菌血管瘤病和人类沟槽发烧的新兴传染剂。危及生命的巴顿病毒并发症可能包括心内膜炎，肾上腺炎肝炎，复发性菌血症，脑病和神经肾上腺炎。这项研究模型Bartonella Quintana目前正在城市无家可归者和患有艾滋病的患者中重新出现。像所有Bartonella一样，B。Quintana在循环系统上定居，在该系统中，它感染了人类红细胞，血管内皮细胞，触发血管生成并引起持续性菌血症。尽管有这些显着的属性，但对巴顿菌的分子发病机理知之甚少。由于Hemin是所有Bartonella物种的基本生长因子，而金蛋白芽孢杆菌具有任何细菌已知的最大Hemin需求，因此这项研究的远距离目标是检查HEMIN获取的分子基础，这一过程不仅会导致在Arthropod载体和人类宿主中建立感染，而且有助于其持续存在。为此，该提案着重于对编码B. Quintana的主要Hemin受体和四个同源物的五基因家族的分析。特定的目标1将使用RT-PCR响应变化的HEMIN浓度来量化HBP表达。我们还将使用电泳迁移率分析和DNA足迹分析潜在的铁摄取调节剂（Fur）框，并将绘制HBP转录起始位点。我们还将通过量化毛皮突变体和过表达的皮毛背景中的HBP表达来验证毛皮在HBP调节中的作用。在特定的目标2中，将分析HBP多基因家族在人类虱子载体和猕猴灵长类动物模型中的表达模式。另外，将生成主要的HBP基因的突变形式和反式汇总菌株，以测试灵长类动物模型中的分子Koch假设。在特定的目标3中，我们将使用生化和遗传方法通过绘制功能受体结构域来确定HBP蛋白的结构和功能。此外，我们将确定HBP是否可以运输Hemin，并确定该功能所需的域。这些数据将提供有关涉及Bartonella增长和持久性基本过程的多基因家族的宝贵信息。此外，由于Bartonella HBP的可能是来自几种革兰氏阴性细菌的外膜家族的成员，因此这项研究产生的数据无疑对细菌发病机理至关重要。