Metallobiochemistry of innate immunity and bacterial physiology

先天免疫的金属生物化学和细菌生理学

• 批准号: 9436092
• 负责人: ELIZABETH M NOLAN
• 金额: $ 27.99万
• 依托单位: MASSACHUSETTS INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-20 至 2021-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9436092
• 关键词: Address; Affect; Affinity; Antimicrobial Resistance; Applications Grants; Bacterial Infections; Bacterial Physiology; Bioavailable; Biochemical Genetics; Bioinorganic Chemistry; Biological Availability; Biology; Calgranulin A; Caring; Chelating Agents; Chronic; Clinical; Coculture Techniques; Communities; Cystic Fibrosis; Data; Development; Disease; Environment; Epithelial Cells; Equipment and supply inventories; Etiology; Extracellular Space; Foundations; Future; Gene Expression; Goals; Growth; Hereditary Disease; Heritability; Homeostasis; Host Defense; Human; Hypoxia; Immune; Immunity; Immunocompromised Host; Immunologic Factors; Individual; Infection; Innate Immune System; Investigation; Ions; Iron; Leukocyte L1 Antigen Complex; Life; Lung; Manganese; Maps; Mediating; Metals; Microbe; Microbial Biofilms; Modeling; Mono-S; Morbidity - disease rate; Mucous body substance; Natural Immunity; Nutrient; Nutritional; Organism; Outcome; Oxidation-Reduction; Oxygen; Pathogenesis; Patients; Physiology; Population; Process; Proteins; Pseudomonas aeruginosa; Pulmonary Cystic Fibrosis; Pulmonary Fibrosis; Quality of life; Research; Research Proposals; Respiratory physiology; Role; S100A8 gene; S100A9 gene; Site; Staphylococcus aureus; Starvation; Structure; System; Testing; Therapeutic; Thick; Transition Elements; United States; Work; Zinc; antimicrobial; bacterial genetics; base; cystic fibrosis patients; design; diabetic; expectation; improved; insight; metal chelator; microbial; microorganism; neutrophil; novel diagnostics; novel therapeutic intervention; oxidation; pathogen; patient population; response; uptake

PROJECT SUMMARY The primary objective of this research initiative is to evaluate how the metal-sequestering human host-defense protein calprotectin (CP) affects metal homeostasis and physiology of bacterial pathogens. Metal ions are essential nutrients for all organisms, and pathogens must acquire these nutrients from the host to replicate and cause infection. During this process, the human innate immune system works to limit the bioavailability of transition metals including manganese (Mn), iron (Fe), and zinc (Zn) by deploying CP and other metal- sequestering proteins at sites of infection. CP is accepted to withhold Mn(II) and Zn(II) from microbial pathogens, and we recently demonstrated that CP coordinates Fe in the reduced ferrous oxidation state. Bacterial systems for Fe(II) acquisition are increasingly appreciated as critical for pathogenesis in multiple infection states, including chronic, biofilm-mediated infections where oxygen becomes limiting. However, no other host-defense proteins that limit Fe(II) have been identified; thus investigating CP as an Fe(II)- sequestering host-defense protein is important for understanding host-pathogen interactions in chronic infection states. Pseudomonas aeruginosa (Pa) and Staphylococcus aureus (Sa) are two human pathogens that cause chronic polymicrobial infections in diverse patient populations, including lung infections in individuals with cystic fibrosis (CF). This hereditary disease predisposes individuals to life-long pulmonary infections, marked by debilitating exacerbations that reduce lung function. Notably, the CF lung becomes increasingly hypoxic as disease progresses, and multiple lines of evidence indicate that Fe(II) becomes the predominant form of bioavailable Fe. Progression of CF lung disease is also correlated with a shift in microbial etiology, with Sa being the predominant microorganism in younger patients, and subsequent Pa colonization associated with lung function decline. The underlying biology that causes this population shift remains poorly understood; however, recent studies suggest that both Fe and CP contribute to this process. We hypothesize that CP limits Fe(II) availability in hypoxic environments, as found in the CF lung, and that this activity eventually allows Pa to outcompete Sa in polymicrobial environments. In Aim 1, we will evaluate Fe(II) sequestration by CP, and map the distribution of metal ions in Pa and Sa cultures treated with CP. In Aim 2, we will test the hypothesis that CP limits Fe(II) to Pa and Sa, and thereby impacts the individual physiologies and co-culture dynamics of these two pathogens. These investigations will enable future studies that address how CP and Fe drive the progression of CF lung infections, and may guide the design and development of novel diagnostic, preventative, and therapeutic approaches to treat bacterial infections.

项目概要 这项研究计划的主要目标是评估金属螯合人类宿主防御 蛋白质钙卫蛋白 (CP) 影响细菌病原体的金属稳态和生理学。金属离子是 所有生物体必需的营养物质，病原体必须从宿主获取这些营养物质才能复制和 引起感染。在此过程中，人类先天免疫系统会限制其生物利用度 通过部署 CP 和其他金属，生产包括锰 (Mn)、铁 (Fe) 和锌 (Zn) 在内的过渡金属 在感染部位隔离蛋白质。 CP 被认为可以阻止微生物接触 Mn(II) 和 Zn(II) 病原体，我们最近证明 CP 在还原的亚铁氧化态中协调 Fe。 人们越来越认识到，获取 Fe(II) 的细菌系统对于多种疾病的发病机制至关重要。 感染状态，包括氧气变得有限的慢性、生物膜介导的感染。然而，没有 已鉴定出其他限制 Fe(II) 的宿主防御蛋白；因此研究 CP 作为 Fe(II)- 隔离宿主防御蛋白对于了解慢性病中宿主与病原体的相互作用非常重要 感染状态。铜绿假单胞菌 (Pa) 和金黄色葡萄球菌 (Sa) 是两种人类病原体 导致不同患者群体的慢性多种微生物感染，包括肺部感染 患有囊性纤维化（CF）的个体。这种遗传性疾病使个体容易患上终生肺部疾病 感染，其特征是使人衰弱的病情加重，导致肺功能下降。值得注意的是，CF 肺变得 随着疾病的进展，缺氧现象越来越严重，多种证据表明 Fe(II) 成为 生物可利用铁的主要形式。 CF 肺部疾病的进展也与微生物的变化相关 病因学，年轻患者中 Sa 是主要微生物，随后 Pa 定植 与肺功能下降有关。导致这种人口转变的潜在生物学仍然很差 明白了；然而，最近的研究表明 Fe 和 CP 都有助于这一过程。我们假设 CP 限制了缺氧环境中 Fe(II) 的可用性，如 CF 肺中所发现的那样，并且这种活性 最终使得 Pa 在多种微生物环境中战胜 Sa。在目标 1 中，我们将评估 Fe(II) CP 的螯合，并绘制了经 CP 处理的 Pa 和 Sa 培养物中金属离子的分布图。在目标 2 中， 我们将检验以下假设：CP 将 Fe(II) 限制为 Pa 和 Sa，从而影响个体生理机能 以及这两种病原体的共培养动态。这些调查将使未来的研究能够解决 CP 和 Fe 如何驱动 CF 肺部感染的进展，并可能指导设计和开发 治疗细菌感染的新诊断、预防和治疗方法。