PHYSICAL BIOCHEMISTRY, PROTEINS, & MOLECULAR RECOGNITION

我们研究的长期目标是了解 蛋白质序列和高级结构与功能之间的联系。在 在过去的五年里，我们研究了蛋白质内部的相互作用;具体来说， 电子交换器的N-和C-末端螺旋之间的界面 蛋白质细胞色素c（Cc）。在未来五年，我们希望利用我们的 专业知识，以朝着新的方向前进，并研究 蛋白质也是。 理解蛋白质之间的相互作用是理解 信号转导是几乎所有生物学过程的关键 从发育到癌症。 了解内部的相互作用 蛋白质对于解释基因组计划的数据至关重要， 设计具有医学有用功能的新型蛋白质。理解 生物电子转移是重要的，因为遗传缺陷， 电子转移蛋白被认为在衰老和 退化性疾病 蛋白质之间。将检查三种复合物：Cc/细胞色素c 过氧化物酶（CCP）、Cc/黄素-细胞色素b2和Cc/细胞色素b5。目前 没有详细的平衡热力学数据， 复杂，因此，拟议的研究将导致新的和重要的 关于分子识别的信息。平衡结合数据将是 使用等温滴定量热法和电子转移法获得 费率将由我们的合作者Millett &达勒姆进行衡量。三 假设将被测试：1）疏水接触控制强度 结合，但离子相互作用控制电子转移的速率; 2） 在以前提出的复合物结构模型中的接触是 对结合和电子转移都很重要; 3）弱的Cc结合 CCP上的位点控制电子转移。绑定数据也将 用于测试最近关于表面积作用的几个假设， 蛋白质复合物形成中的溶剂化。 在蛋白质中。我们将检验一个被广泛接受的观点， 包含很少的，如果有的话，特定的天然长程相互作用。我们有 最近表明，N-和C-末端螺旋之间的相互作用 存在于熔融的球状体中我们现在建议绘制 血红素6 Os螺旋和C末端螺旋。 平衡 变性的热力学将使用微分 扫描量热法

The long range goal of our research is to understand the relationships between protein sequence and higher order structure and function. In the past five years we examined interactions within a protein; specifically, the interface between the N- and C-terminal helices of the electron trader protein cytochrome c (Cc). In the next five years we wish to use our expertise to move in a new direction and study interactions between proteins as well. Understanding interactions between proteins is the key to understanding signal transduction, a process essential to nearly all biological processes from development to cancer. Understanding interactions within proteins is crucial for interpreting the data from genome projects and designing novel proteins with medically useful functions. Understanding biological electron transfer is important because genetic defects in electron transfer proteins are thought to play a role in aging and in degenerative diseases. Between proteins. Three complexes will be examined: Cc/cytochrome c peroxidase (CCP), Cc/flavo-cytochrome b2, and Cc/cytochrome b5. Currently there are no detailed equilibrium thermodynamic data on any of these complexes, so the proposed research will lead to new and important information about molecular recognition. Equilibrium binding data will be obtained using isothermal titration calorimetry and electron transfer rates will be measured by our collaborators Millett & Durham. Three hypotheses will be tested: 1) hydrophobic contacts control the strength of binding, but ionic interactions control the rate of electron transfer; 2) contacts in the previously proposed structural models of the complexes are important for both binding and electron transfer; 3) a weak Cc binding site on CCP dominates electron transfer. The binding data will also be used to test several recent hypotheses about the role of surface area and solvation in protein complex formation. Within proteins. We will test the widely held belief that molten globules contain few, if any, specific native long range interactions. We have recently shown that the interaction between the N- and C-terminal helices persists in the molten globule. We now propose to map interactions between the heme, the 6Os helix and the C-terminal helix. The equilibrium thermodynamics of denaturation will be measured using differential scanning calorimetry.