RADIATION INDUCED LIPID AND SULFHYDRYL AUROXIDATION

辐射诱导的脂质和巯基氧化

• 批准号: 3188523
• 负责人: MICHAEL Douglas SEVILLA
• 金额: $ 7.22万
• 依托单位: OAKLAND UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1987
• 资助国家: 美国
• 起止时间: 1987-07-01 至 1990-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3188523
• 关键词: autooxidation; biological models; free radicals; hydroxyl group; lipids; oxidized lipid; peroxides; radiation sensitivity; singlet oxygen; spectrometry

This project proposes a study of the radiation induced autoxidation of selected lipids and sulfur compounds of biological importance, including the chemistry, structure and motion of the resulting peroxyl radicals. Electron Spin Resonance (ESR) spectroscopy, and ab initio and semiempirical molecular orbital calculations will be employed to elucidate the relationships between structure, motion and reactivity in these systems. Our proposed project intends to focus on the following aspects of lipid and sulfur oxy radical chemistry; Elucidation, through ESR spectroscopy, of the details of the autoxidation cycle in a number of unsaturated and saturated lipids at low temperatures. In this work kinetic analyses of the rates of build up and loss of the radicals involved in lipid autoxidation as a function of temperature will be performed to find the activation energies for both oxygen mobilization, and hydrogen abstraction by lipil peroxyl radicals. Next investigation of lipid peroxyl radicals formed in lipids with increasing unsaturation will be performed to observe the effect of unsaturation on the motional averaging of the peroxyl probe. The role of sulfuroxygen radicals in autoxidation processes will be studied. Using techniques developed in our laboratory, we will determine the identify of the radical(s) formed when thiols and disulfides are irradiated in the presence of oxygen at low temperatures, and determine the importance of these radicals to the autoxidation of sulfur containing compounds. Theoretical as well as experimental characterization of the sulfur oxygen radicals will be performed. Preliminary investigations of the role of sulfuroxygen radicals in lipid oxidation will be initiated. Ab initio (Gaussian B2) and semiempirical molecular orbital calculations will be employed to develop and test models of lipid and sulfur oxy radical structure, motion, and reactivity.

该项目提出了一项研究， 选择的脂类和硫化合物的自氧化 重要性，包括化学，结构和运动的 产生过氧自由基。 电子自旋共振（ESR） 光谱，从头算和半经验分子轨道 计算将被用来阐明的关系 结构，运动和反应性之间的联系 我们 拟议的项目打算侧重于以下方面的脂质 和硫氧自由基化学;通过ESR解析 光谱，在一些自动氧化循环的细节 不饱和和饱和的脂质在低温下。 在这 工作动力学分析的速度建立和损失的 自由基参与脂质自动氧化， 温度将进行，以找到活化能为 氧的移动和氢的提取 过氧自由基 脂质过氧自由基的研究进展 在脂质中形成的不饱和度增加， 观察不饱和度对运动平均的影响， 过氧化氢探针 硫氧自由基的作用 将研究自氧化过程。 使用技术 在我们的实验室开发的，我们将确定的识别 当硫醇和二硫化物被辐射时， 在低温下的氧的存在，并确定 这些自由基对硫自氧化的重要性 含有化合物。 理论和实验 将进行硫氧自由基的表征。 硫氧自由基在细胞内作用的初步研究 将引发脂质氧化。 从头算（高斯B2）和 半经验分子轨道计算将被用来 开发和测试脂质和硫氧自由基结构的模型， 运动和反应性。