DYNAMICS & INTERPROTEIN INTERACTIONS IN RELEASE OF IRON IN BACTERIOFERRITIN

动力学

• 批准号: 8359665
• 负责人: Mario Rivera
• 金额: $ 6.78万
• 依托单位: UNIVERSITY OF KANSAS LAWRENCE
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-04-01 至 2012-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8359665
• 关键词: Binding; Complex; Computing Methodologies; Coupled; Deuterium; Disease; Electron Transport; Enteral; Ferredoxin; Ferritin; Funding; Grant; Haemophilus influenzae; Homeostasis; Hydrogen; Invaded; Iron; Metabolism; Methods; Molecular; NMR Spectroscopy; National Center for Research Resources; Nutrient; Organism; Oxidoreductase; Physiological; Principal Investigator; Process; Property; Proteins; Pseudomonas aeruginosa; Research; Research Infrastructure; Resources; Respiratory Tract Infections; Shigella dysenteriae; Signal Transduction; Source; Toxic effect; United States National Institutes of Health; antimicrobial; bacterioferritin; cost; improved; pathogen; prevent; protein structure function; uptake

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Organisms causative of diseases such as respiratory tract infections (Haemophilus influenzae), enteric conditions (Shigella dysenteriae) and the opportunistic Pseudomonas aeruginosa have developed sophisticated mechanisms for sequestering iron from their host. This intense competition between invading pathogens and their host for the nutrient has led to the idea that new antimicrobials may target iron acquisition and homeostasis. To study this idea more closely, it is important to gain molecular-level understanding of the mechanisms by which pathogens manage iron, from acquisition and internalization to storage and utilization. Significant advances have improved our understanding of iron uptake by P. aeruginosa and many other pathogens. In comparison, little is known about the fate of internalized iron. One mechanism whereby iron toxicity is controlled is by storage of iron in ferritin and bacterioferritin, which are large proteins capable of storing up to 4,000 iron atoms in their internal cavities. Despite the importance of ferritins and bacterioferritins in regulating iron concentrations and preventing its toxic effects, little is known about the processes that deliver Fe2+ for storage or the signals that prompt its release for safe integration in metabolism. We have recently demonstrated that mobilization of Fe2+ from bacterioferritin A (BfrA) in P. aeruginosa requires electron transfer from a ferredoxin reductase (FPR). Thus the BfrA-FPR complex is an unprecedented opportunity to investigate how bacterioferritins recognize their physiological regulators and if binding modulates the dynamic properties of the bacterioferritin to facilitate iron release. To fill these gaps we plan to: (1) Investigate the dynamic properties of BfrA utilizing a strategy specifically tailored to study large proteins using hydrogen/deuterium H/D exchange coupled to NMR spectroscopy. (2) Investigate the dynamic properties of BfrA with the aid of computational methods and (3) Utilize computational and HD/NMR methods to investigate how BfrA binds to FPR and determine the effect that the inter-protein association exerts on the dynamic properties of BfrA.

该子项目是利用资源的众多研究子项目之一 由 NIH/NCRR 资助的中心拨款提供。子项目的主要支持 并且子项目的主要研究者可能是由其他来源提供的， 包括其他 NIH 来源。 子项目可能列出的总成本 代表子项目使用的中心基础设施的估计数量， NCRR 赠款不直接向子项目或子项目工作人员提供资金。 引起呼吸道感染（流感嗜血杆菌）、肠道疾病（痢疾志贺氏菌）和机会性铜绿假单胞菌等疾病的生物体已经发展出复杂的机制，可以从宿主体内螯合铁。入侵病原体与其宿主之间对营养物质的激烈竞争催生了新的抗菌药物可能以铁的获取和体内平衡为目标的想法。为了更仔细地研究这个想法，重要的是从分子水平上了解病原体管理铁的机制，从获取和内化到储存和利用。重大进展提高了我们对铜绿假单胞菌和许多其他病原体吸收铁的了解。相比之下，人们对内化铁的命运知之甚少。 控制铁毒性的一种机制是通过将铁储存在铁蛋白和细菌铁蛋白中，它们是大型蛋白质，能够在其内腔中储存多达 4,000 个铁原子。尽管铁蛋白和细菌铁蛋白在调节铁浓度和防止其毒性作用方面很重要，但人们对输送 Fe2+ 进行储存的过程或促使其释放以安全整合到代谢中的信号知之甚少。我们最近证明，铜绿假单胞菌中细菌铁蛋白 A (BfrA) 中 Fe2+ 的动员需要铁氧还蛋白还原酶 (FPR) 的电子转移。因此，BfrA-FPR 复合物为研究细菌铁蛋白如何识别其生理调节因子以及结合是否调节细菌铁蛋白的动态特性以促进铁释放提供了前所未有的机会。 为了填补这些空白，我们计划：（1）利用氢/氘 H/D 交换与 NMR 光谱相结合的专门用于研究大蛋白质的策略来研究 BfrA 的动态特性。 (2) 借助计算方法研究 BfrA 的动态特性； (3) 利用计算和 HD/NMR 方法研究 BfrA 如何与 FPR 结合，并确定蛋白质间缔合对 BfrA 动态特性的影响。