XAS STUDIES ON HEME PROTEINS

血红素蛋白的 XAS 研究

• 批准号: 8170188
• 负责人: PETER A LAY
• 金额: $ 0.75万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-05-01 至 2011-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8170188
• 关键词: Binding; Brain; Cardiovascular Diseases; Cardiovascular system; Cells; Cerebral Ischemia; Computer Retrieval of Information on Scientific Projects Database; Data; Dioxygenases; Funding; Grant; Health; Heme; Heme Group; Hemeproteins; Human; Hypertension; Institution; Kidney; Ligands; Myoglobin; Nature; Neurodegenerative Disorders; Neurons; Procedures; Proteins; Research; Research Personnel; Resources; Role; Source; Spectrum Analysis; Stroke; Structure; Subcellular structure; Techniques; Tryptophan; United States National Institutes of Health; absorption; adduct; blood pressure regulation; in vivo; indoleamine; neuroglobin; oxidation

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Heme proteins have been studied extensively by x-ray absorption spectroscopy, but new proteins/roles continue to emerge. XANES and multiple-scattering XAFS studies are sensitive probes of their oxidation state, coordination number and the nature of the coordinating ligands. We will study the heme structures with respect to the roles of neuroglobin (Nb) in the brain, NO binding and other functions of myoglobin (Mb) in cardiovascular disease, and the new protein, indoleamine 2,3-dioxygenase-2 (IDO-2), in the kidneys. We will use these techniques to compare the structures of different adducts and oxidation states of the isolated proteins with those contained within cells. In particular, whether Nb confers neuro-protection during cerebral ischemia is controversial and we plan to study changes in the structures of intracellular neuroglobin in neurons under normal conditions and those associated with stroke and neurodegenerative diseases. Similarly, NO binding to Mb is important in the health of the cardiovascular system, but it is uncertain as to whether it binds to the thiolate group, the heme centre or both in human Mb in vivo. We will compare the XAS data from isolated proteins with those found in cells under various conditions associated with normal conditions and those associated with cardiovascular disease. Finally, the recently discovered IDO-2 metabolizes tryptophan, like the well-studied IDO (now known as IDO-1). However, IDO-2, unlike IDO-1, loses its activity when the protein is isolated and purified. XAS will be used to study the structural changes that occur during the isolation procedures in order to ascertain the likely active structure in vivo. This is important as there is mounting evidence that IDO-2 in the kidney has a role in controlling blood pressure and, hence, understanding the nature of the active form and how its activity may be modulated to control blood pressure has many potential applications in the treatment of both low and high blood pressure.

该子项目是利用该技术的众多研究子项目之一 资源由 NIH/NCRR 资助的中心拨款提供。子项目及 研究者 (PI) 可能已从 NIH 的另一个来源获得主要资金， 因此可以在其他 CRISP 条目中表示。列出的机构是 对于中心来说，它不一定是研究者的机构。 血红素蛋白已通过 X 射线吸收光谱进行了广泛研究，但新的蛋白质/作用不断出现。 XANES 和多重散射 XAFS 研究是其氧化态、配位数和配位配体性质的敏感探针。我们将研究血红素结构，包括神经红蛋白 (Nb) 在大脑中的作用、NO 结合和肌红蛋白 (Mb) 在心血管疾病中的其他功能，以及肾脏中的新蛋白质吲哚胺 2,3-双加氧酶-2 (IDO-2)。我们将使用这些技术来比较分离蛋白质与细胞内所含蛋白质的不同加合物的结构和氧化态。特别是，铌在脑缺血期间是否具有神经保护作用尚存在争议，我们计划研究正常条件下以及与中风和神经退行性疾病相关的神经元中细胞内神经红蛋白结构的变化。同样，NO 与 Mb 的结合对于心血管系统的健康很重要，但尚不确定它在体内是否与人 Mb 中的硫醇基团、血红素中心或两者结合。我们将比较分离蛋白质的 XAS 数据与在与正常条件相关和与心血管疾病相关的各种条件下的细胞中发现的数据。最后，最近发现的 IDO-2 可以代谢色氨酸，就像经过充分研究的 IDO（现在称为 IDO-1）一样。然而，与 IDO-1 不同，IDO-2 在分离和纯化蛋白质时会失去活性。 XAS 将用于研究分离过程中发生的结构变化，以确定体内可能的活性结构。这一点很重要，因为越来越多的证据表明肾脏中的 IDO-2 在控制血压方面发挥着作用，因此，了解其活性形式的性质以及如何调节其活性以控制血压在治疗低血压和高血压方面具有许多潜在的应用。