SPECTROSCOPY OF BIOLOGICAL SATURATED PORPHYRINS

生物饱和卟啉的光谱学

• 批准号: 3285515
• 负责人: THOMAS M LOEHR
• 金额: $ 15.81万
• 依托单位: OREGON GRADUATE INSTITUTE SCIENCE & TECH
• 依托单位国家: 美国
• 财政年份: 1984
• 资助国家: 美国
• 起止时间: 1984-12-01 至 1991-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3285515
• 关键词: Escherichia coli; Neurospora; Pseudomonas aeruginosa; Raman spectrometry; catalase; chlorin; chlorophyll; circular magnetic dichroism; diol; hemoprotein; lactones; lactoperoxidase; ligands; metal complex; metalloenzyme; metalloporphyrins; molecular site; myoglobin; nitrites; nuclear magnetic resonance spectroscopy; oxidation reduction reaction; porphyrin biosynthesis; porphyrin structure; protein reconstitution; thyroid inhibitor; Escherichia coli; Neurospora; Pseudomonas aeruginosa; Raman spectrometry; catalase; chlorin; chlorophyll; circular magnetic dichroism; diol; hemoprotein; lactones; lactoperoxidase; ligands; metal complex; metalloenzyme; metalloporphyrins; molecular site; myoglobin; nitrites; nuclear magnetic resonance spectroscopy; oxidation reduction reaction; porphyrin biosynthesis; porphyrin structure; protein reconstitution; thyroid inhibitor

This project concerns the investigation of the detailed prosthetic group structure of chlorin and saturated porphyrin-containing proteins and enzymes. In the previous grant period, we established characteristic and definitive infrared (IR) and resonance Raman (RR) spectral properties of metallochlorins that are consistently diagnostic for the chlorin macrocycle in biological and model systems. In the current proposal we propose to extend those studies to the following systems: 1) The green heme d terminal oxidase from E. coli is proposed to be either a diol chlorin or a lactone chlorin. We will examine the RR spectra of the purified E. coli heme d complex in its various spin- and oxidation-states in comparison with diol and lactone substituted model complexes to determine the in vivo structure of the heme d macrocycle. 2) The green form of myoglobin (Mb) induced by exposure to sulfur compounds, sulfMb, has a sulfur-modified iron chlorin prosthetic group. The mammalian enzymes lactoperoxidase (LPO) and thyroid peroxidase (TPO) are inhibited by sulfur drugs known as goitrogens, in a reaction similar to that which leads to the formation of sulfMb. We propose to determine whether the prosthetic group of sulfLPO is indeed a sulf-chlorin, and elucidate the structural origin of the observed UV-vis spectral differences between sulfLPO and sulfMb. We will also extend the studies on sulfchlorin systems to include the stable, extractable sulfhemes from sulfMb, and if possible sulfLPO, as well as model sulfchlorin complexes. 3) We will purify the cytochrome cd1 bacterial nitrite reductase from Ps. aeruginosa and isolate the green heme d1 prosthetic group to examine spectral characteristics of dioxoisobacteriochlorins (porphyrindione). We will compare the properties of the purified cd1 enzyme and its isolated d1 prosthetic group with those of a variety of positional and substitutional isomers of oxo-chlorin and dioxo-iBC model complexes. 4) We plan to extend these studies to the analysis of sirohemes and more highly saturated porphyrins, e.g., tetrahydroporphyrins and hexahydroporphyrins, to establish spectral properties which are specific for each level of saturated porphyrin. 5) Myoglobin and other heme proteins will be reconstituted with iron chlorin complexes. We will examine the spectral properties of these chlorin-proteins in all accessible spin- and oxidation-states, as well as ligand complexes, in comparison with the protein-free model complexes.

该项目涉及对详细假肢的调查 氯蛋白和饱和卟啉的组结构 蛋白质和酶。 在上一个赠款期间，我们 已建立的特征和确定的红外（IR）和 金属氯蛋白的共振拉曼（RR）光谱特性 始终是氯蛋白大环的诊断 生物和模型系统。 在当前的建议中，我们提出 将这些研究扩展到以下系统：1）绿色 提议来自大肠杆菌的血红素D末端氧化酶是A 二醇氯蛋白或内酯氯化物。 我们将检查RR光谱 纯化的大肠杆菌血红素复合物的各种自旋和 与二醇和内酯取代的氧化态相比 模型复合物以确定血红素D的体内结构 大环。 2）由肌红蛋白（MB）的绿色形式 暴露于硫化合物的硫mb具有硫酸化的铁 氯素假体。 哺乳动物酶 抑制乳糖氧化酶（LPO）和甲状腺过氧化物酶（TPO） 通过称为goitrogens的硫药物，在类似的反应中 导致形成硫。 我们建议确定 硫磺的假体是否确实是硫酸盐， 并阐明观察到的UV-VIS光谱的结构起源 Sulflpo和SulfMB之间的差异。 我们还将扩展 关于硫氯肽系统的研究，包括稳定的，可提取的 硫磺的硫磺，如果可能的话 硫氯酸酯络合物。 3）我们将净化细胞色素CD1 PS的细菌亚硝酸盐还原酶。铜绿和隔离 绿色血红素D1假体以检查光谱 二氧化四局的特征（斑点杆菌）。 我们 将比较纯化的CD1酶及其的性质 孤立的D1假肢与各种位置 以及氧 - 氯蛋白和二氧化物IBC模型的替代异构体 复合物。 4）我们计划将这些研究扩展到分析 Sirohemes和更高度饱和的卟啉，例如 四氢戊丁蛋白和六氢戊烯丁物，以建立 光谱特性，特定于每个饱和级别 卟啉。 5）肌红蛋白和其他血红素蛋白将是 用铁氯素复合物重构。 我们将检查 这些氯蛋白蛋白在所有可访问的自旋中的光谱特性 - 相比之下 与无蛋白质模型复合物。