RUI: Phosphorescence Probe of Heme Protein Dynamics

9417885 Schuh寻求对球状蛋白质的动态内部运动的详细理解，因为其对于蛋白质的结构/功能关系的知识的重要性，因为它们涉及基础研究和涉及蛋白质药物的生产和药物的逻辑设计的工业研究的应用方面。 主要研究者和学生报告说，6-溴-2-萘基硫酸盐（BNS）的磷光被血红素蛋白质的血红素特异性地猝灭。 猝灭的速率常数kq是由激光诱导磷光的寿命测量确定的，并用于判断血红素蛋白的内部运动使血红素环可接近的程度。 在本研究中，将尝试用更大的磷光分子探针（例如9-溴-6-菲硫酸盐）代替BNS。 还将测量作为温度和溶剂条件的函数的几种酶促和非酶促血红素蛋白的kq。 %最终目标是：1）估计蛋白质中瞬时波动的大小，2）确定酶促和非酶促血红素蛋白的动力学是否存在根本差异，3）比较天然蛋白质和蛋白质折叠中的一种重要中间体（称为熔融球）的动力学，4）深入了解血红素蛋白复合物中血红素的可及性，以及5）确定血红蛋白的三级结构动力学是否对分子氧的结合和释放重要。 ***

9417885 Schuh A detailed understanding of the dynamic internal motion of globular proteins is sought because of its importance to a knowledge of the structure/function relationships of proteins as they pertain to fundamental research and to applied aspects of industrial research involving production of protein pharmaceuticals and the logical design of drugs. The principal investigator and students have reported that the phosphorescence of 6-bromo-2-naphthyl sulfate (BNS) is quenched specifically by the heme of heme proteins. The rate constant for quenching, kq, is determined from lifetime measurements of laser-induced phosphorescence and is used to judge the extent to which internal motion of heme proteins makes the heme rings accessible. In this research attempts will be made to substitute larger phosphorescent molecular probes (e.g. 9-bromo-6- phenanthrene sulfate) in place of BNS. Also kq will be measured for several enzymatic and non-enzymatic heme proteins as a function of temperature and solvent conditions. %%% The ultimate goals are to: 1) estimate the size of transient fluctuations in proteins, 2) determine whether there are fundamental differences in the dynamics of enzymatic and non- enzymatic heme proteins, 3) compare the dynamics of native proteins and an important intermediate in protein folding, called the molten globule, 4) gain insight into the accessibility of the hemes in heme protein complexes, and 5) determine whether tertiary structural dynamics of hemoglobin is important to the binding and release of molecular oxygen. ***