Bioinorganic Explorations of Host-Defense Proteins

宿主防御蛋白的生物无机探索

• 批准号: 9239551
• 负责人: ELIZABETH M NOLAN
• 金额: $ 26.96万
• 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: 2017-08-15 至 2021-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9239551
• 关键词: Affinity; Animal Model; Antibiotics; Binding; Bioavailable; Biochemical; Biological; Biological Assay; Biological Process; Biophysics; C-terminal; Calcium; Cations; Chelating Agents; Chemistry; Communicable Diseases; Crystallization; Data; Development; Dimerization; Disease; Divalent Cations; EF Hand Motifs; EF-Hand Domain; Electron Spin Resonance Spectroscopy; Epithelial Cells; Exhibits; Extracellular Space; Growth; Health; Homeostasis; Host Defense; Human; Human Pathology; Immune response; Infection; Inflammation; Innate Immune Response; Innate Immune System; Intercept; Invaded; Investigation; Ions; Iron; Knowledge; Leukocyte L1 Antigen Complex; Literature; Malignant Neoplasms; Manganese; Medical; Metals; Methods; Microbe; Modeling; Molecular; Morbidity - disease rate; Mus; NMR Spectroscopy; Natural Immunity; Nutrient; Organism; Outcome; Pathogenesis; Physiological; Play; Process; Property; Proteins; Public Health; Research Proposals; Role; Rosaniline Dyes; S100 Proteins; S100A8 gene; S100A9 gene; Sepsis; Site; Spin Labels; Staphylococcus aureus; Streptococcus pneumoniae; Structure; Tail; Testing; Transition Elements; United States; Work; Zinc; antimicrobial; base; chelation; dimer; extracellular; foodborne; host-microbe interactions; innovation; insight; member; metal chelator; microbial; neutrophil; novel strategies; pathogen; prevent; response; solute; therapeutic development; therapeutic target

PROJECT SUMMARY Transition metal ions are essential nutrients for all organisms. The availability of these nutrients plays a critical role in the host-microbe interaction and microbial pathogenesis. The primary objective of this research proposal is to elucidate how the host-defense protein calprotectin (CP) sequesters transition metals from microbes and thereby contributes to the innate immune response. CP provides a remarkable example of unique biological coordination chemistry that is relevant to infectious disease and microbial pathogenesis. Each CP heterodimer (S100A8/S100A9) exhibits six different sites for chelating divalent cations, including calcium (Ca) and transition metals. Our central hypothesis is that CP responds to physiological Ca(II) gradients to tune its coordination chemistry for transition metals and to modulate its biological function as an antimicrobial protein that deprives invading pathogens of essential nutrient metals (e.g. manganese, iron, zinc). The proposed investigations are based on preliminary data that Ca(II) binding by human CP (hCP) at the EF- hand domains triggers high-affinity chelation of transition metals at sites formed at the interface of the S100A8 and S100A9 subunits. In Aim 1, we will investigate how Ca(II) ions modulate hCP structure and tune its affinities for transition metals. In Aim 2, we will evaluate how the murine orthologue (mCP) sequesters transition metals and thereby provide needed molecular and biophysical insights into literature results of CP from animal models of infection. In Aim 3, we will investigate the competition between CP and bacterial metal- transport machinery for manganese(II). These fundamental bioinorganic and biophysical initiatives constitute an innovative departure from biological and medical studies of CP, and highlight the importance of applying quantitative analytical and spectroscopic methods to a problem central to human health and disease. Taken together, the results will provide new molecular insights into how CP contributes to innate immunity and metal homeostasis. Moreover, the ability to acquire metal ions is an important facet of microbial pathogenesis, and both intercepting microbial metal acquisition and boosting the metal-withholding response of the host present opportunities for antibiotic development. We anticipate that the results from our work will, in the long term, help to guide the development of new antimicrobial therapeutics that target these processes central to the host- pathogen interaction.

项目概要 过渡金属离子是所有生物体必需的营养物质。这些营养素的可用性至关重要 在宿主-微生物相互作用和微生物发病机制中的作用。本研究的主要目的 该提案旨在阐明宿主防御蛋白钙卫蛋白（CP）如何隔离过渡金属 微生物，从而有助于先天免疫反应。 CP 提供了一个显着的例子 与传染病和微生物发病机制相关的独特的生物配位化学。 每个 CP 异二聚体 (S100A8/S100A9) 具有六个不同的二价阳离子螯合位点，包括 钙 (Ca) 和过渡金属。我们的中心假设是 CP 对生理 Ca(II) 有反应 梯度来调整其过渡金属的配位化学并调节其作为过渡金属的生物功能 抗菌蛋白，可剥夺入侵病原体的必需营养金属（例如锰、铁、锌）。 拟议的研究基于初步数据，即 Ca(II) 与人 CP (hCP) 在 EF- 处结合。 手结构域在 S100A8 界面处形成的位点触发过渡金属的高亲和力螯合 和S100A9亚基。在目标 1 中，我们将研究 Ca(II) 离子如何调节 hCP 结构并调整其 过渡金属的亲和力。在目标 2 中，我们将评估小鼠直系同源物 (mCP) 如何隔离 过渡金属，从而为 CP 的文献结果提供所需的分子和生物物理见解 来自感染的动物模型。在目标 3 中，我们将研究 CP 和细菌金属之间的竞争- 锰(II)运输机械。这些基本的生物无机和生物物理举措构成了 与 CP 的生物学和医学研究的创新背离，并强调应用的重要性 定量分析和光谱方法解决人类健康和疾病的核心问题。采取 总之，这些结果将为 CP 如何促进先天免疫和金属提供新的分子见解。 体内平衡。此外，获取金属离子的能力是微生物发病机制的一个重要方面，并且 既能拦截微生物对金属的获取，又能增强宿主对金属的保留反应 抗生素开发的机遇。我们预计，从长远来看，我们的工作成果将有助于 指导针对宿主核心过程的新抗菌疗法的开发 病原体相互作用。