Function of MVFR in Pseudomonas aeruginosa virulence

MVFR 在铜绿假单胞菌毒力中的作用

• 批准号: 7613448
• 负责人: LAURENCE G RAHME
• 金额: $ 38.09万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-04-01 至 2011-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7613448
• 关键词: 4-Aminobenzoic Acid; Aminobenzoic Acids; Anabolism; Animal Model; Animals; Anthranilic Acids; Anti-Infective Agents; Antibiotics; Attenuated; Bacteremia; Bacteria; Bacterial Infections; Binding; Binding Sites; Biochemical; Blood; Burn injury; Cell Communication; Cell Culture Techniques; Cells; Complex; Cystic Fibrosis; Cytochromes; Development; Disease Outbreaks; Doctor of Philosophy; Drosophila melanogaster; Enzymes; Exhibits; Genes; Goals; Growth; HIV; Healthcare; Hospitals; Human; Immune; Immunity; Incidence; Infection; Injection of therapeutic agent; Laboratories; Ligand Binding; Ligand Binding Domain; Ligands; Lung; Magnetic Resonance Imaging; Mammals; Manuscripts; Mediating; Modeling; Molecular Genetics; Multi-Drug Resistance; Mus; Neonatal; Nosocomial Infections; Nucleic Acid Regulatory Sequences; Operon; Organ; Pathway interactions; Patients; Pharmaceutical Preparations; Play; Proteins; Pseudomonas; Pseudomonas aeruginosa; Publishing; Quinolones; Regulation; Regulatory Pathway; Research Personnel; Resistance development; Respiratory Tract Infections; Role; Sepsis; Signal Transduction; Signaling Molecule; Skin; Structure; Testing; Therapeutic; Thick; Time; Tissues; Toxic effect; Transcription Coactivator; Virulence; Virulence Factors; bacterial resistance; base; clinically relevant; cystic fibrosis patients; genetic analysis; heat injury; in vivo; inhibitor/antagonist; mortality; mutant; novel; outcome forecast; pathogen; pathogenic bacteria; pressure; prevent; programs; promoter; quorum sensing; research study; respiratory; transcription factor

DESCRIPTION (provided by applicant): Infections caused by Pseudomonas aeruginosa are a significant problem in human healthcare. This bacterial pathogen is the principle agent of sepsis in burn patients; of persistent lung infections and mortality in cystic fibrosis patients; of nosocomial infections in HIV and other immune-suppressed patients; and of the outbreak of deleterious multi-drug resistant infections in hospitals. The long-term goal of this proposal is to provide effective and selective therapies that reduce the incidence and complications of human P. aeruginosa infections. This study proposes this goal can be achieved by drugs that prevent or limit the activation of the MvfR/HAQ pathway, and the development of such anti-infective compounds is the immediate goal of this application. This proposal is based on the hypothesis that MvfR, a P. aeruginosa transcriptional regulator, is a candidate target for anti-infective drugs, as it plays a central role in modulating the expression of many QS-controlled virulence-associated factors; and its activation is mediated by its binding to a specific ligand, which is essential for its function. To identify MvfR-pathway inhibitors, and demonstrate their in vivo anti-infective activity, this study proposes three Specific Aims: 1) to confirm the identity of the MvfR ligand, identify its binding site, and determine its mechanism of action; 2) to identify compounds that inhibit the MvfR/HAQ pathway; and 3) to determine the in vivo efficacy and potential feasibility of these inhibitors to limit P. aeruginosa infection in mammals. These aims will be accomplished via three sets of experiments. First, biochemical, mass spectrometric, and molecular genetic analyses will confirm the identity of the P. aeruginosa MvfR-ligand; define the MvfR ligand binding domain; and determine the pqsA promoter sequence recognized and bound by MvfR and the MvfR-ligand complex. Second, biochemical and mass spectrometric analyses will identify compounds that prevent ligand-mediated MvfR activation by limiting the synthesis and/or binding of its ligand, and that are metabolically stable in P. aeruginosa. Third, each identified inhibitor will be tested in the Drosophila melanogaster, the mouse full-thickness skin thermal injury, and the mouse neonatal respiratory model, to determine their toxicity, their in vivo efficacy to limit P. aeruginosa infection; and their "immunity" to the development of bacterial resistance. Specific inhibition of a pathway that directly mediates virulence is less likely to generate selective pressure to develop resistance to the inhibitor, than for drugs, including most antibiotics, that reduce bacterial viability. Such targeted inhibitors could significantly enhance the long-term prognosis of burn, cystic fibrosis, and HIV patients. To this end, the results here should enable novel therapies to treat and/or prevent P. aeruginosa-human infections.

描述（由申请人提供）：铜绿假单胞菌引起的感染是人类医疗保健中的一个重要问题。这种细菌病原体是烧伤患者败血症的主要药物。囊性纤维化患者的持续性肺部感染和死亡率；艾滋病毒和其他免疫抑制患者的医生感染；以及医院中有害多药物抗性感染的爆发。该提案的长期目标是提供有效和选择性的疗法，以减少铜绿假单胞菌感染的发生率和并发症。这项研究提出，可以通过预防或限制MVFR/HAQ途径激活的药物来实现此目标，而这种抗感染化合物的发展是该应用的直接目标。该建议基于以下假设：铜绿假单胞菌转录调节剂MVFR是抗感染药物的候选靶标，因为它在调节许多QS控制的毒力相关因素的表达方面起着核心作用。它的激活是由其与特定配体的结合介导的，这对于其功能至关重要。为了鉴定MVFR-Pathway抑制剂，并证明其体内抗感染活性，本研究提出了三个具体目的：1）确认MVFR配体的身份，识别其结合位点并确定其作用机理； 2）确定抑制MVFR/HAQ途径的化合物； 3）确定这些抑制剂限制哺乳动物中铜绿假单胞菌感染的体内功效和潜在的可行性。这些目标将通过三组实验来实现。首先，生化，质谱和分子遗传分析将确认铜绿假单胞菌MVFR-ligand的身份；定义MVFR配体结合域；并确定由MVFR和MVFR配体复合物识别和结合的PQSA启动子序列。其次，生化和质谱分析将通过限制其配体的合成和/或结合来鉴定可以防止配体介导的MVFR激活的化合物，并在铜绿假单胞菌中代谢稳定。第三，每个鉴定的抑制剂将在果蝇果蝇，小鼠全厚度皮肤热损伤和小鼠新生儿呼吸模型中进行测试，以确定其毒性，其体内功效以限制铜绿假单胞菌感染；以及它们对细菌抗性发展的“免疫力”。与降低细菌生存能力的药物相比，对直接介导毒力的途径的特异性抑制不太可能产生对抑制剂的抗性的选择性压力，而不是降低细菌生存能力的药物。这种靶向抑制剂可以显着增强烧伤，囊性纤维化和HIV患者的长期预后。为此，这里的结果应使新型疗法能够治疗和/或预防铜绿假单胞菌 - 人类感染。