Mbdes Fe和Hbdes Fe内的氧分布与迁移。多频相位和调制荧光测定法研究。
Oxygen distribution and migration within Mbdes Fe and Hbdes Fe. Multifrequency phase and modulation fluorometry study.
作者信息
Jameson D M, Gratton E, Weber G, Alpert B
出版信息
Biophys J. 1984 Apr;45(4):795-803. doi: 10.1016/S0006-3495(84)84224-1.
Quenching of the intensity and lifetime of porphyrin fluorescence from Mbdes Fe and Hbdes Fe (iron-free myoglobin and hemoglobin) by oxygen was investigated using a multifrequency cross-correlation phase fluorometer. The single exponential decay characteristic of porphyrin emission of Mbdes Fe and Hbdes Fe became doubly exponential upon application of oxygen pressure. The results were interpreted in terms of a general model of dynamic quenching of fluorescence in globular proteins. The model accounted for the rate k+ of acquisition of quencher by the protein, the exit rate k- of quencher from the protein, and the migration rate chi of quencher in the protein interior. The values of k+, k-, and chi were different for Mbdes Fe and Hbdes Fe. The addition of 40% sucrose, which increased the bulk viscosity sixfold, modified these rates. These results are discussed and compared with previous quenching studies on proteins. The significance of these results and the model for the interpretation of protein quenching studies is emphasized.
使用多频互相关相位荧光计研究了氧气对无铁肌红蛋白（Mbdes Fe）和无铁血红蛋白（Hbdes Fe）中卟啉荧光强度和寿命的猝灭作用。施加氧气压力后，Mbdes Fe和Hbdes Fe中卟啉发射的单指数衰减特征变为双指数衰减特征。研究结果依据球状蛋白质中荧光动态猝灭的通用模型进行了解释。该模型考虑了蛋白质获取猝灭剂的速率k+、猝灭剂从蛋白质中逸出的速率k-以及猝灭剂在蛋白质内部的迁移速率χ。Mbdes Fe和Hbdes Fe的k+、k-和χ值各不相同。添加使体积粘度增加六倍的40%蔗糖会改变这些速率。对这些结果进行了讨论，并与之前关于蛋白质的猝灭研究进行了比较。强调了这些结果以及该模型对蛋白质猝灭研究解释的重要性。
Zotero 插件