TIME RESOLVED AND LOW TEMPERATURE RAMAN INVESTIGATION OF HEME PROTEINS

这项研究将联合收割机的资源， 实验室，以产生一个完整的研究动态 复合物中球蛋白、血红素和配体之间相互作用 双分子血红蛋白 亚稳态血红素瞬时物种将是 通过皮秒的配体（O2，NO，CO）光解产生， 纳秒脉冲激光源。 这些物种的动态 将在时间尺度上进行探测，从皮秒到毫秒， 我们已经建立了拉曼和吸收技术， laboratories. 各种球蛋白和溶液的作用 将确定双生子重组动力学的条件 皮秒瞬态吸收光谱 结构性 共振拉曼光谱的特异性将使我们能够 检查这个复杂系统中的单个分子坐标， 低温技术将使我们能够确定 参与近端和远端血红素袋的松弛 随后分别进行配体光解和再结合。 的 大量的数据有关的平衡结构的 血红蛋白分子，加上大量的球蛋白， 已知的扰动，提供了预期，它将是 可以解释复杂的时间和温度分辨数据 在分子的“化学动力学”层面上。 这是一个独特 生物物理学和技术的机会， 时间分辨拉曼和吸收光谱学的专业知识， 在我们的实验室里， 可行

This study will combine the resources of two established laboratories to produce a complete study of the dynamics of interaction between globin, heme, and ligand in a complex bimolecule, hemoglobin. Metastable heme transient species will be generated via ligand (02, NO, CO) photolysis by picosecond and nanosecond pulsed laser sources. The dynamics of these species will be probed on timescales, from picosecs to millisecs using both Raman and absorption techniques already established in our laboratories. The effects of various globins and solution conditions on geminate recombination kinetics will be determined with picosecond transient absorption spectroscopy. The structural specificity of resonance Raman spectroscopy will allow us to examine individual molecular coordinates in this complex system and cryogenic techniques will allow us to determine the energetics involved in the relaxation of the proximal and distal heme pockets subsequent to ligand photolysis and rebinding respectively. The large body of data concerning the equilibrium structures of the hemoglobin molecules, coupled with the large number of globins with known perturbations, provides for the expectation that it will be possible to interpret complex time and temperature resolved data on a molecular, "chemical dynamics" levels. This is a unique opportunity in biophysics and the technology and demonstrated expertise in time-resolved Raman and absorption spectroscopies now available in our laboratories makes such an undertaking eminently feasible.