RESONANCE RAMAN STUDIES OF HEME PROTEINS

我们观察到了详细的和信息量丰富的共振拉曼光谱 血红素蛋白细胞色素P450和细胞色素引起的近紫外线激光 激动人心。我们建议将我们的测量扩展到可见光，使用 我们的可调谐染料激光器，进一步利用谐波进入紫外光 产生和光学多道分析器(OMA)检测。我们计划 重点研究了重要催化剂的拉曼光谱 中间态，如还原和氧化的P450络合物 以帮助推断参与氧结合和裂解的机制 这类重要的代谢酶。长期目标是 利用共振拉曼散射获得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置结构和功能 为了更好地理解金属卟啉的光吸收 光谱。光敏中间态将使用OMA进行研究 检测和我们的双臂拉曼差分光谱仪将使用 在涉及低温的各种实验中，同位素 标签、pH和压力扰动等。理论含义 将进一步研究三体简正振荡器模型，并 基于“变换”的吸收和拉曼激发相关理论 轮廓测量将应用于血红素蛋白系统，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最新开发的 绝对量子产额测定技术。光声 光谱学将用来帮助我们理解这些荧光 实验和伴随的快速无辐射弛豫通道 存在于血红素蛋白系统中。

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.