Periplasmic Zinc Management and Homeostasis in Paracoccus denitrificans

脱氮副球菌的周质锌管理和稳态

基本信息

批准号：
10078950
负责人：
Erik T Yukl
金额：
$ 26.64万
依托单位：
NEW MEXICO STATE UNIVERSITY LAS CRUCES
依托单位国家：
美国
项目类别：
财政年份：
2018
资助国家：
美国
起止时间：
2018-01-01 至 2022-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10078950
关键词：
ATP Hydrolysis ATP phosphohydrolase ATP-Binding Cassette Transporters Affinity Animal Model Antibiotic Resistance Antibiotics Antimicrobial Resistance Attenuated Bacteria Binding Binding Proteins Cell membrane Centers for Disease Control and Prevention (U.S.)Citrobacter koseri Crystallization Data Development Drug Targeting Environment Family Genes Genetic Genome Glycine decarboxylase Growth Health Histidine Homeostasis Homologous Gene Homologous Protein Kinetics Klebsiella aerogenes Klebsiella pneumoniae Knock-out Lead Lipoproteins Membrane Metals Modeling Molecular Chaperones Molecular Target Multi-Drug Resistance Nosocomial Infections Nutrient Operon Organism PAWR protein Paracoccus denitrificans Pathogenesis Periplasmic Proteins Phenotype Physiological Pilot Projects Prevalence Process Production Proteins Publishing Resolution Role Salmonella enterica Sequence Homology Specificity Streptococcus pneumoniae Structure Substrate Specificity System Techniques Transition Elements Virulence Work X-Ray Crystallography Zinc antibiotic resistant infections base biophysical techniques carbapenem resistance combat design emerging antibiotic resistance flexibility human pathogen improved in vivo inhibitor/antagonist insight knockout gene multi-drug resistant pathogen mutant novel pathogen pathogenic bacteria peptidomimetics periplasm permease preference solute stoichiometry uptake

项目摘要

ABSTRACT The prevalence of antibiotic resistance among pathogenic bacteria has become a major health concern and has spurred the search for novel antibiotic targets. A particularly promising target is the superfamily of bacterial ATP-binding cassette (ABC) transporters, which couple the hydrolysis of ATP to the transport of a wide variety of solutes across the cell membrane. Bacterial ABC transporters work in conjunction with a high affinity solute binding protein (SBP) that specifically binds substrate and delivers it to the transporter. In Salmonella enterica and Streptococcus pneumoniae among others, disruption of genes encoding ABC transporters and SBPs specific for Zn dramatically attenuates virulence in animal models, highlighting these systems as potent drug targets. We have identified two Zn-specific ABC transporter operons in Paracoccus denitrificans, ZnuABC and AztABCD, and have characterized a hitherto hypothetical protein (AztD) that acts as a Zn chaperone, directly transferring Zn to the SBP of that system (AztC). This project will utilize P. dentrificans as a model for highly homologous systems in human pathogens belonging to the carbapenem-resistant Enterobacteriacaea (CRE). These organisms are associated with broad- spectrum antimicrobial resistance and are the causative agents of potentially deadly nosocomial infections. We will determine the precise mechanism of metal binding and transfer for AztC and AztD proteins from P. denitrificans and the CRE pathogen Citrobacter koseri using structural and biophysical techniques. The physiological roles of the Azt and Znu systems will be determined by making genetic knockouts of these genes in P. denitrficans and characterizing growth deficient phenotypes in Zn-limited medium. High-resolution structural information combined with in vivo functionality will yield new insight into the mechanisms of transition metal import in bacteria and potentially provide a basis for the rational design of metal uptake inhibitors as antibiotics for multi- drug resistant pathogens. !

抽象的病原菌抗生素耐药性盛行已成为重大健康问题的关注并刺激了对新抗生素靶标的寻找。一个特别有希望的目标是细菌 ATP 结合盒 (ABC) 转运蛋白超家族，耦合水解 ATP 参与多种溶质跨细胞膜的运输。细菌ABC 转运蛋白与高亲和力溶质结合蛋白 (SBP) 协同工作，该蛋白特异性地结合底物并将其输送至转运蛋白。肠道沙门氏菌和链球菌肺炎链球菌等，编码 ABC 转运蛋白和 SBP 的基因被破坏锌可显着减弱动物模型中的毒力，凸显这些系统是有效的药物目标。我们在脱氮副球菌中鉴定出了两个 Zn 特异性 ABC 转运蛋白操纵子， ZnuABC 和 AztABCD，并表征了迄今为止假设的蛋白质 (AztD)，其作用为 Zn 伴侣，直接将 Zn 转移到该系统的 SBP (AztC)。该项目将利用 P. dentrificans 作为人类病原体高度同源系统的模型，属于耐碳青霉烯类肠杆菌（CRE）。这些生物体与广泛的谱抗菌药物耐药性，是潜在致命的医院感染的病原体感染。我们将确定 AztC 和金属结合和转移的精确机制使用结构和方法从脱氮假单胞菌和 CRE 病原体科塞柠檬酸杆菌中提取 AztD 蛋白生物物理技术。 Azt 和 Znu 系统的生理作用将由以下因素决定对脱氮假单胞菌中的这些基因进行基因敲除并表征生长缺陷限锌培养基中的表型。高分辨率结构信息结合体内功能将为细菌和过渡金属输入机制提供新的见解可能为金属摄取抑制剂作为抗生素的合理设计提供基础。耐药病原体。！