LOW FREQUENCY MODES & THEIR ROLE IN EQUILIBRATION

振动跃迁对温度（频率）敏感 位移和带宽变化），因此我们正在开发瞬态IR 研究蛋白质和其他结构中热传递的方法 水溶液。 特别地，水的IR光谱是 通过加热使氢键断裂而改性， 方法可以测量CA的变化。 0.02 C.目前计划 实验由能量流动引起的温度变化 从血红素组进行了研究。 加热步骤也可以通过以下方式实现： 通过红外线脉冲 具体而言，作为一个 用于该技术试验床是Mb、Hb和Cyt-C衍生物，其具有 不同的配体。 在光激发后，配体可以 分离 解离能可以直接用于加热 直接的环境，但能量保留为内部振动 能量是受限制的。 一些能量可以被释放或消耗， 与配体解离相关的蛋白质结构变化。 的 释放的热能主要用于激发低频模式 周围的环境。 目前还没有答案， 在血红素处释放的热量流经蛋白质， 周围的水。 例如，蛋白质是否具有可测量的各向同性 还是热扩散率各向异性？ 能源是否 在蛋白质的特定全局结构区域的瓶颈？ 可以 我们找到了一个定量的理论描述， 创建 热 光谱？ 这些问题可以通过以下方式直接解决： 探测H2O和蛋白质中跃迁的红外光谱， 具有已知的温度依赖性。

Vibrational transitions are sensitive to temperature (frequency shifts and bandwidth changes) so we are developing transient IR methods to study heat transport in proteins and other structures in aqueous solutions. In particular, the IR spectrum of water is modified by heating which breaks hydrogen bonds and the proposed methods can measure changes of ca. 0.02 C. In currently planned experiments the changes in temperature arising from the flow of energy from a heme group is studied. The heating step might also be effected by means of an infrared pulse. Specifically, the system proposed as a test bed for this technology are Mb, Hb and Cyt-C derivatives having different ligands. After optical excitation, the ligand may dissociate. The energy of dissociation can go directly to heating the immediate surroundings but the energy retained as internal vibrational energy is bottlenecked. Some energy may be released or consumed in protein structural changes associated with ligand dissociation. The released thermal energy is used to excite mainly low frequency modes of the surroundings. There are not yet answers to how the energy released at the heme flows through the protein which ultimately heats the surrounding H2O. For example, is the protein measurably isotropic or anisotropic in regard to its thermal diffusivity? Does energy bottleneck in specific global structural regions of the protein? Can we find a quantitative theoretical description of the initially created hot spectra? These questions can be addressed directly by probing the IR spectra of transitions in the H2O and the protein that have known temperature dependence.