Roles of Phosphate Uptake in Pneumococcal Antibiotic Resistance and Virulence

磷酸盐吸收在肺炎球菌抗生素耐药性和毒力中的作用

• 批准号: 8302505
• 负责人: MALCOLM E. WINKLER
• 金额: $ 23.09万
• 依托单位: TRUSTEES OF INDIANA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-02-01 至 2014-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8302505
• 关键词: ATP-Binding Cassette Transporters; Address; Animal Model; Antibiotic Resistance; Antibiotics; Area; Attenuated; Bacteria; Bacterial Model; Bacterial Physiology; Biological Process; Cell surface; Culture Media; Data; Development; Disease; Disease Progression; Divalent Cations; Escherichia coli; Future; Genetic; Goals; Gram-Positive Bacteria; Grant; Health; Homeostasis; Human; Human Resources; Immunocompromised Host; In Vitro; Individual; Infection; Ions; Lactams; Link; Literature; Little' s Disease; Manganese; Metabolism; Metals; Methods; Modeling; Molecular Genetics; Monobactams; Mus; Mutation; Pathogenesis; Physiology; Play; Pneumococcal Colonization; Pneumococcal Infections; Population; Pump; Regulation; Regulon; Research; Resistance; Risk; Role; Route; Spectrum Analysis; Streptococcus; Streptococcus pneumoniae; Stress; System; Testing; Time; Toxic effect; Virulence; Work; Zinc; base; divalent metal; experience; in vivo; inorganic phosphate; insight; meetings; mutant; pathogen; pathogenic bacteria; resistance mechanism; respiratory; tool; uptake; vaccine development

DESCRIPTION (provided by applicant): Streptococcus pneumoniae (pneumococcus) is a major human respiratory pathogen that remains a serious health threat worldwide. Resistance of S. pneumoniae to multiple antibiotics is increasing at an alarming rate, and the population of immunocompromised individuals who are at risk for pneumococcal invasive diseases continues to grow. Relatively little is known about the roles played by pneumococcal physiology and metabolism in promoting colonization and virulence of its human host. The overall goal of this grant is to explore the roles played by inorganic phosphate (Pi) uptake and its regulation in the pathogenesis, antibiotic resistance, and metal ion homeostasis of S. pneumoniae. Pi uptake has already been implicated in pneumococcal invasive disease, but little is known about the mechanisms underlying this involvement. Several pieces of evidence show that the regulation of Pi transport in S. pneumoniae is fundamentally different from the mechanisms determined previously for model bacteria, like E. coli and B. subtilis. Therefore, this grant will challenge te current paradigms of Pi uptake that are based on these model bacterial systems and relate Pi uptake to the pathogenesis of S. pneumoniae for the first time. In addition, this work will validat and explore a new mechanism of pneumococcal ¿-lactam resistance about which nothing is known. Finally, this grant draws together several recent ideas from the scientific literature to formulate the hypothesis that cellular Pi uptake and Pi cellular amount are tied to the availabilit and toxicity of several key divalent cations, including zinc (Zn2+) and manganese (Mn2+). Four Specific Aims will be met by this grant. Aim 1 will determine whether two predicted Pi ABC transporter pumps (designated as Pst1 and Pst2) separately uptake Pi in S. pneumoniae and whether this uptake is coordinated. Another goal of Aim 1 is to develop a powerful genetic toolbox and a conceptual framework about Pi uptake and its regulation that will allow effective exploration of the topics in Aims 2-4. Aim 2 will determine the roles of the Pst1 and Pst2 Pi transporters and the likely regulators (designated as PnpRS, PhoU1, and PhoU2) in pneumococcal colonization and virulence. Aim 2 will also determine whether there are additional routes of Pi uptake during infection, besides Pst1 and Pst2. Aim 3 will determine whether increased expression of the Pst1 transporter is responsible for resistance to ¿-lactam antibiotics and whether the Pst2 transporter also plays a role. Aim 4 will explore whether there are links between Pi uptake and cellular amount and divalent metal ion homeostasis. There is a high likelihood of obtaining publishable data from this work that will serve as the basis for a future RO1 application and open up a significant new research area in S. pneumoniae. In addition, this grant has the potential to provide new targets for antibiotic and vaccine development and to provide information about an uncharacterized mechanism of ¿-lactam antibiotic resistance in this important opportunistic pathogen. PUBLIC HEALTH RELEVANCE: The Gram-positive bacterium Streptococcus pneumoniae (pneumococcus) is a major human respiratory pathogen to which antibiotic resistance is increasing at an alarming rate. The overall goal of this grant is to explore the roles played by inorganic phosphate (Pi) uptake and its regulation in the pathogenesis, antibiotic resistance, and metal homeostasis of Streptococcus pneumoniae. Besides providing insights into important biological processes, this grant has the potential to provide new cell-surface targets for antibiotc and vaccine development and to provide new information about an uncharacterized mechanism of ¿-lactam antibiotic resistance in this opportunistic primary pathogen.

描述（由适用提供）：肺炎链球菌（肺炎球菌）是人类主要的呼吸病原体，在全球范围内仍然是严重的健康威胁。肺炎链球菌对多种抗生素的耐药性正在以惊人的速度增加，并且有肺炎球菌侵袭性疾病风险的免疫功能低下的个体人口继续增长。关于肺炎球菌生理学和代谢在促进其人类宿主的殖民化和病毒中所扮演的角色相对鲜为人知。该赠款的总体目标是探索无机磷酸盐（PI）摄取及其在发病机理，抗生素耐药性和肺炎链球菌的金属离子稳态中所扮演的角色。 PI摄取已经在肺炎球菌侵袭性疾病中浸渍了，但是对这种参与的基础机制知之甚少。几个证据表明，肺炎链球菌中PI转运的调节与先前针对模型细菌（如大肠杆菌和枯草芽孢杆菌）确定的机制根本不同。因此，该赠款将挑战基于这些模型细菌系统的PI摄取的当前范式，并首次将PI摄取与肺炎链球菌的发病机理相关。此外，这项工作将有效并探索肺炎球菌的新机制 - lactam耐药性，据何时了解。最后，这笔赠款将科学文献的最新思想汇总在一起，以提出这样的假设，即细胞摄取和PI细胞量与几种关键偏见阳离子的可用性和毒性相关，包括锌（Zn2+）和曼甘尼斯（MN2+）。这笔赠款将满足四个具体目标。 AIM 1将确定两个预测的PI ABC转运蛋白泵（指定为PST1和PST2）是否在肺炎链球菌中分别摄取PI，以及这种摄取是否是协调的。目标1的另一个目标是开发一个强大的遗传工具箱和有关PI吸收及其法规的概念框架，该框架将有效探索AIM 2-4中的主题。 AIM 2将确定PST1和PST2 PI转运蛋白以及可能的调节剂（指定为PNPRS，PHOU1和PHOU2）在肺炎定植和病毒中的作用。 AIM 2还将确定除了PST1和PST2，在感染过程中是否还有其他PI吸收途径。 AIM 3将确定PST1转运蛋白的表达增加是否负责抗lactam抗生素的耐药性以及PST2转运蛋白是否也起作用。 AIM 4将探索PI吸收与细胞量与二价金属离子稳态之间是否存在联系。从这项工作中获取可发布数据的很有可能是将来的RO1应用程序的基础，并在S. Pneumoniae开设了一个重要的新研究领域。此外，该赠款有潜力为抗生素和疫苗发育提供新的靶标，并提供有关这种重要机会病原体中未表征的 - lactam抗生素耐药性的信息。 公共卫生相关性：革兰氏阳性细菌肺炎链球菌（肺炎球菌）是一种主要的人类呼吸道病原体，抗生素耐药性以惊人的速度增加。该赠款的总体目标是探索无机磷酸盐（PI）摄取及其在发病机理，抗生素耐药性和肺炎链球菌的金属稳态中所扮演的角色。除了提供有关重要生物过程的见解外，该赠款还具有为抗替代物和疫苗发育提供新的细胞表面靶标，并提供有关这种机会性原发性病原体中未经特色机制的新信息。