Heme utilization and homeostasis in Pseudomonas aeruginosa

铜绿假单胞菌的血红素利用和稳态

基本信息

批准号：
8774579
负责人：
Angela Wilks
金额：
$ 38.38万
依托单位：
UNIVERSITY OF MARYLAND BALTIMORE
依托单位国家：
美国
项目类别：
财政年份：
2012
资助国家：
美国
起止时间：
2012-12-01 至 2015-11-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8774579
关键词：
Antibiotic Resistance Antibiotics Biliverdine Binding Proteins Biochemical Bioinformatics Biological Assay Devices Equilibrium Feedback Gene Expression Regulation Genetic Gram-Negative Bacterial Infections Health Heme Heme Iron Homeostasis Hospitals In Vitro Indwelling Catheter Infection Iron Isomerism Metabolic Metabolic Pathway Metabolism Modeling Molecular Molecular Chaperones Morbidity - disease rate Multi-Drug Resistance Mutation Natural Resistance Nosocomial Infections Operon Organism Oxygenases Pathway interactions Play Protein Conformation Protein Dynamics Proteins Pseudomonas aeruginosa RNA Regulation Regulatory Pathway Role Sepharose Signal Pathway Site-Directed Mutagenesis Small RNA Source Staging Structure System Testing Therapeutic Therapeutic Intervention Virulence antimicrobial biophysical analysis combat extracellular heme oxygenase-2 heme-binding protein in vivo insight meetings metabolomics mortality new therapeutic target novel novel strategies novel therapeutics pathogen pathogenic bacteria pressure protein complex protein transport research study trafficking uptake

项目摘要

DESCRIPTION (provided by applicant): Pathogenic bacteria require iron for their survival and ability to cause infection. Many bacterial pathogens have evolved sophisticated systems to utilize heme as a primary source of iron. The opportunistic pathogen P. aeruginosa is an increasingly common cause of nosocomial infections with high morbidity associated with such infections. In addition to their natural resistance to many antibiotics the alarming increase in such infections highlights the need for alternate antimicrobial strategies. In previous biochemical and biophysical studies we have characterized the intracellular heme trafficking protein PhuS and the iron-regulated heme oxygenase HemO and have further shown they are critical for heme utilization and virulence. The specific aims of the proposal are to further elucidate the mechanism of extracellular heme utilization and regulation as it relates to virulence. This will be achieved through; i) Elucidating the intracellular heme trafficking pathway and defining the role of biliverdin IX-delta and -beta isomers in the extra-cellular feedback regulation of heme uptake through genetic, biochemical, and metabolomics approaches. ii) Defining the mechanism of heme transfer from PhuS to HemO through a combination of site-directed mutagenesis, biochemical and biophysical studies and iii) Determining the role of the regulatory small RNA PrrH in heme uptake and utilization. These studies will provide new insights into heme and iron homeostasis in bacterial pathogens. We will through this proposal identify new heme metabolic and regulatory pathways as novel antimicrobial targets and advance the current understanding of heme transfer mechanisms.

描述（由申请人提供）：致病菌需要铁才能生存并具有引起感染的能力。许多细菌病原体已经进化出复杂的系统来利用血红素作为铁的主要来源。机会性病原体铜绿假单胞菌是医院内感染日益常见的原因，且与此类感染相关的发病率很高。除了它们对许多抗生素的天然耐药性之外，此类感染的惊人增加凸显了替代抗菌策略的必要性。在之前的生化通过生物物理学研究，我们对细胞内血红素运输蛋白 PhuS 和铁调节血红素加氧酶 HemO 进行了表征，并进一步表明它们对于血红素利用和毒力至关重要。该提案的具体目的是进一步阐明细胞外血红素利用和调节与毒力相关的机制。这将是通过实现； i) 通过遗传、生化和代谢组学方法阐明细胞内血红素运输途径，并定义胆绿素 IX-delta 和 β 异构体在血红素摄取的细胞外反馈调节中的作用。 ii) 通过定点诱变、生化和生物物理研究相结合，确定血红素从 PhuS 转移到 HemO 的机制，以及 iii) 确定调节性小 RNA PrrH 在血红素摄取和利用中的作用。这些研究将为细菌病原体中的血红素和铁稳态提供新的见解。我们将通过这项提案确定新的血红素代谢和调节途径作为新的抗菌靶点，并增进目前对血红素转移机制的理解。