PlrSR-dependent Signal Transduction in Bordetella Virulence

博德特氏菌毒力中 PlrSR 依赖性信号转导

基本信息

批准号：
10097965
负责人：
Peggy A Cotter
金额：
$ 49.79万
依托单位：
UNIV OF NORTH CAROLINA CHAPEL HILL
依托单位国家：
美国
项目类别：
财政年份：
2017
资助国家：
美国
起止时间：
2017-03-06 至 2023-02-28
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10097965
关键词：
Adolescent and Young Adult Aerobic Affect Affinity Air Anaerobic Bacteria Bacteria Binding Binding Sites Biochemical Biological Bordetella Bordetella bronchiseptica Bordetella pertussis Carbon Dioxide Cell Survival Cells Cessation of life ChIP-seq Child Country DNA Sequence Data Deoxyribonuclease I Developed Countries Developing Countries Development Disease EMSA Epitopes Family Gene Activation Gene Expression Gene Expression Profile Gene Expression Regulation Genes Genetic Genetic Recombination Heme Human Immunity Immunization Immunize In Vitro Incidence Individual Infant Infection Light Link Lower respiratory tract structure Mammals Mediating Modeling Molecular Mus Nasal cavity Oxidases Oxidation-Reduction Oxides Oxygen Pathogenesis Pertussis Pertussis Vaccine Phosphoric Monoester Hydrolases Phosphotransferases Population Protein Family Proteins Public Health Rattus Regulation Risk Role Signal Transduction Structural Genes System Testing United States Vaccinated Vaccination Vaccines Virulence Virulence Factors base cytochrome c oxidase diagnostic assay experimental study genetic approach genome-wide in vitro activity in vivo inorganic phosphate insight member novel diagnostics novel therapeutics novel vaccines pathogen prevent promoter protein function respiratory pathogen response therapeutic target transmission process

项目摘要

Summary/Abstract: Pertussis (aka whooping cough) is a serious reemerging public health problem with incidence estimated at 20 million cases annually and deaths (mostly in infants) at ~200,000 annually. Recent rises in pertussis in countries with high vaccine coverage, such as the United States, correlate with a switch from whole cell (wP) to acellular (aP) pertussis vaccines and are attributed to a larger reservoir of infected individuals composed of adolescents and young adults who were vaccinated (rather than infected) as children. It is now apparent that immunity induced by aP vaccination is not as durable as vaccination by wP vaccination, which is not as durable as immunity induced by infection with Bordetella pertussis, the primary causal agent of pertussis. Moreover, while immunization with wP and aP vaccines provides protection against disease (at least initially), it does not protect against colonization. New vaccines that provide sterilizing, long-lasting immunity are needed. We have discovered a previously uncharacterized signal transduction system (PlrSR) that is required for B. pertussis and the closely-related broad host range pathogen Bordetella bronchiseptica to colonize and persist in the lower respiratory tract (LRT). Our preliminary data support a model in which PlrSR functions as a kinase in response to increased CO2 and low oxygen conditions (reflective of the LRT), resulting in high levels of PlrR-phosphate (PlrR~P) that activate expression of genes including those encoding high-affinity cytochrome oxidases. Our model states that under aerobic conditions, PlrS functions primarily as a phosphatase, and that low levels of PlrR~P are essential for cell viability. We will use genetic, molecular biological, and genome-wide approaches to identify PlrSR-regulated genes, especially those induced only in the LRT, and will determine the roles of PlrSR-dependent gene regulation and of the factors encoded by the regulated genes in virulence. Using genetic approaches, we will determine the role of the PlrS PDC and PAS domains, as well as the predicted kinase and phosphatase activities of PlrS, in the ability of the bacteria to grow in vitro and in the LRT. Using biochemical approaches, we will determine if PlrS is a redox- sensitive heme-containing protein that functions as a kinase under low oxygen conditions and a phosphatase in ambient air, and we will identify DNA sequences to which PlrR~P binds. Our results will be significant because previously unknown PlrSR-dependent virulence factors, and the PlrSR system itself, will be excellent candidates for the development of new component vaccines and targets for the development of new therapeutics. Our results will also advance our understanding NtrYX family proteins (of which PlrSR is a member and which control virulence in other pathogens) function and they will provide insight into how respiratory pathogens, in general, grow in the LRT.

摘要/摘要：百日咳（又名百日咳）是一个严重的重新出现的公共卫生问题，估计发病率每年有 2000 万例病例，死亡人数（主要是婴儿）约为 20 万例。近期上涨在美国等疫苗覆盖率较高的国家，百日咳与从全细胞 (wP) 到无细胞 (aP) 百日咳疫苗，归因于受感染的病毒库更大由青少年和年轻人组成的个人，他们接种了疫苗（而不是被感染）孩子们。现在很明显，aP 疫苗接种诱导的免疫力不如 aP 疫苗接种那么持久。 wP 疫苗接种的持久性不如百日咳博德特氏菌感染引起的免疫力，百日咳的主要病原体。此外，虽然使用 wP 和 aP 疫苗进行免疫接种可以提供防止疾病（至少在最初），它不能防止定植。新疫苗需要提供杀菌、持久的免疫力。我们发现了一个以前未表征过的百日咳博德特氏菌和密切相关的广泛宿主所需的信号转导系统（PlrSR）一系列病原体支气管败血博德特氏菌在下呼吸道（LRT）中定植并持续存在。我们的初步数据支持一个模型，其中 PlrSR 作为激酶响应 CO2 增加和低氧条件（反映轻轨），导致高水平的 PlrR-磷酸盐 (PlrR~P) 激活基因的表达，包括编码高亲和力细胞色素氧化酶的基因。我们的模型指出在有氧条件下，PlrS 主要作为磷酸酶发挥作用，并且低水平的 PlrR~P 对于细胞活力至关重要。我们将利用遗传学、分子生物学和全基因组识别 PlrSR 调节基因的方法，特别是那些仅在 LRT 中诱导的基因，并且将确定 PlrSR 依赖性基因调控的作用以及受调控基因编码的因子的作用具有毒力的基因。使用遗传方法，我们将确定 PlrS PDC 和 PAS 的作用细菌能力中的 PlrS 结构域以及预测的激酶和磷酸酶活性在体外和轻轨中生长。使用生化方法，我们将确定 PlrS 是否是氧化还原- 敏感的含血红素蛋白，在低氧条件下充当激酶，并且环境空气中的磷酸酶，我们将识别 PlrR~P 结合的 DNA 序列。我们的结果将是重要的，因为以前未知的 PlrSR 依赖性毒力因子，以及 PlrSR 系统本身将成为开发新成分疫苗和目标的优秀候选者新疗法的开发。我们的结果还将促进我们对 NtrYX 家族蛋白的理解（PlrSR 是其中的成员，控制其他病原体的毒力）发挥作用，并且它们将深入了解呼吸道病原体一般如何在轻轨中生长。