HEME PROTEIN STRUCTURE AND FUNCTION

血红素蛋白结构和功能

• 批准号: 3484889
• 负责人: JACK PEISACH
• 金额: $ 41.44万
• 依托单位: ALBERT EINSTEIN COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-05-01 至 1993-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3484889
• 关键词: DNA; Raman spectrometry; bleomycin; chemical models; chemical structure function; copper; cytochrome P450; drug receptors; electron spin resonance spectroscopy; electron transport; ferredoxin; hemoprotein structure; horses; imidazole; laboratory rat; ligands; magnetic field; metalloproteins; microsomes; oxidoreductase; peroxides; porphyrins; potassium; respiratory oxygen; respiratory oxygenation; root; sodium; transferrin

The work proposed in this competing renewal application is to continue studies on transition metalloproteins and complexes whose metal centers can be probed by various physical techniques. Particular attention will be given to bleomycin (BLM), a glycopeptide antibiotic that cleaves DNA and requires a transition metal for this activity. We will determine that metal ligand in Fe (III)-BLM and activated BLM, elucidating the structure of the coordination site from magnetic field and frequency dependent electron spin echo modulation (ESEEM) studies. We will determine how the structure is change when the drug binds to DNA. We will study the interaction of metallo bleomycins with oligo- and polynucleotides as a means of relating the proposed mechanism of DNA cleavage to the specificity of binding of the drug. With Fe(III)-, activated- and 02Co(II)-BLM, ESEEM studies will be used to determine the distance of the paramagnetic probe to deuterons specifically labelled on polynucleotide sugar. Resonance Raman studies are proposed to elucidate the structure of bound oxygen in an activated belomycin derivative that does not cleave DNA. As fundamental differences have already been seen in the mechanism of Fe-bleomycin action with purified DNA as compare to cell nuclei, experiments are proposed to study the DNA cleavage activity in nuclei and to relate this to the in vitro mechanism. We will assess the requirement for copper in the antibiotic action of BLM in cells where metallothionein level are elevated and copper is sequestered. We will continue the development of electron spin echo envelope modulation (ESEEM) spectroscopy with particular attention to the study of 170, 23NA and 39K interactions with Mn(II)-ATP in kinase, both to quantify the number of interacting nuclei and to determine their distances from the paramagnetic center. Our continuing ESEEM studies with substituted imidazole- 14N interactions with Cu(II), heme, and Fe(III)- tetraphenylporphyrin, models for copper oxidase and mitochondrial cytochrome b, will assess the relative contributions of steric as compared to electronic effects on electron-nuclear coupling.

这项竞争性更新申请中提出的工作是 继续研究过渡金属蛋白和复合物，其 金属中心可以通过各种物理技术探测。 将特别关注博莱霉素 (BLM)，这是一种 糖肽抗生素可切割 DNA 并需要转换 用于此活动的金属。 我们将确定金属配体 Fe (III)-BLM 和活化的 BLM，阐明了结构 配位点与磁场和频率相关 电子自旋回波调制（ESEEM）研究。 我们将确定 当药物与 DNA 结合时结构如何发生变化。 我们将 研究金属博莱霉素与寡聚和 多核苷酸作为关联所提出的机制的手段 DNA 切割对药物结合的特异性。 和 将使用 Fe(III)-、活化-和 02Co(II)-BLM、ESEEM 研究 确定顺磁探针到氘核的距离 专门标记在多核苷酸糖上。 共振拉曼 提出研究以阐明结合氧的结构 一种活化的贝霉素衍生物，不会切割 DNA。 作为 机制上已经出现根本性差异 与细胞核相比，Fe-博莱霉素对纯化 DNA 的作用， 实验旨在研究 DNA 切割活性 细胞核并将其与体外机制联系起来。 我们将 评估 BLM 抗生素作用对铜的需求 在金属硫蛋白水平升高且铜含量升高的细胞中 被隔离。 我们将继续发展电子自旋 回波包络调制 (ESEEM) 光谱学 关注 170、23NA 和 39K 相互作用的研究 激酶中的 Mn(II)-ATP，均用于量化相互作用的数量 原子核并确定它们与顺磁体的距离 中心。 我们对取代咪唑的持续 ESEEM 研究- 14N 与 Cu(II)、血红素和 Fe(III) 相互作用- 四苯基卟啉，铜氧化酶和线粒体模型 细胞色素 b，将评估空间的相对贡献 与电子对电子-核耦合的影响进行比较。