RESONANCE RAMAN STUDIES OF HEME PROTEINS

血红素蛋白的共振拉曼研究

• 批准号: 3072394
• 负责人: Paul M. Champion
• 金额: $ 5.27万
• 依托单位: NORTHEASTERN UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1984
• 资助国家: 美国
• 起止时间: 1984-09-01 至 1989-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3072394
• 关键词: Raman spectrometry; acidity /alkalinity; cytochrome P450; cytochrome c; fluorescence spectrometry; hemoprotein

We have observed detailed and informative resonance Raman spectra from the heme proteins cytochrome P450 and cytochrome causing near ultraviolet laser excitation. We propose to extend our measurements into the visible using our tunable dye laser and further into the ultraviolet using harmonic generation and optical multichannel analyzer (OMA) detection. We plan to specifically focus on Raman spectral studies of important catalytic intermediate states such as the reduced and oxygenated P450 complexes in order to help deduce mechanisms involved in oxygen binding and cleavage in this important class of metabolic enzymes. The long term objective is to use resonance Raman scattering to gain new information about the active site structure and function of cytochrome P450 and other heme proteins and to achieve a better understanding of metalloporphyrin optical absorption spectra. Photosensitive intermediate states will be studied using OMA detection and our dual arm Raman difference spectrometer will be utilized in a variety of experiments involving cryogenic temperatures, isotopic labels, pH and pressure perturbations, etc. The theoretical implications of 3-body normal mode oscillator models will be further pursued and the "transform" based theories relating absorption and Raman excitation profiled measurements will be applied to heme protein systems such as cytochrome c, hemoglobin and cytochrome P450. Fluorescence excitation profile measurements of heme systems will be made using our newly developed technique for absolute quantum yield determination. Photoacoustic spectroscopy will be used to aid in our understanding of these fluorescence experiments and the accompanying rapid nonradiative relaxation channels present in heme protein systems.

我们观察到了详细且信息丰富的共振拉曼光谱 血红素蛋白细胞色素 P450 和细胞色素引起近紫外激光 励磁。 我们建议将我们的测量扩展到可见光 我们的可调谐染料激光器，并使用谐波进一步进入紫外线 生成和光学多通道分析仪 (OMA) 检测。 我们计划 特别关注重要催化的拉曼光谱研究 中间态，例如还原和氧化的 P450 复合物 为了帮助推断参与氧结合和裂解的机制 这一类重要的代谢酶。 长期目标是 使用共振拉曼散射来获取有关活性物质的新信息 细胞色素 P450 和其他血红素蛋白的位点结构和功能以及 更好地了解金属卟啉的光吸收 光谱。 将使用 OMA 研究光敏中间态 将使用我们的双臂拉曼差分光谱仪进行检测 在涉及低温、同位素的各种实验中 标签、pH 值和压力扰动等。理论意义 将进一步追求三体简正模振荡器模型，并且 基于“变换”的吸收和拉曼激发理论 分析测量将应用于血红素蛋白系统，例如 细胞色素 C、血红蛋白和细胞色素 P450。 荧光激发 血红素系统的轮廓测量将使用我们新开发的 绝对量子产率测定技术。 光声 光谱将用于帮助我们理解这些荧光 实验和伴随的快速非辐射弛豫通道 存在于血红素蛋白质系统中。