Saviotti M L, Galley W C
Proc Natl Acad Sci U S A. 1974 Oct;71(10):4154-8. doi: 10.1073/pnas.71.10.4154.
While the phosphorescence of aromatic chromophores in solution is normally quenched through diffusion of dissolved oxygen and other solvent-mediated processes, the phosphorescence of some proteins in solution is observed at room temperature. The tryptophan phosphorescence arises from residues which are hindered from interaction with oxygen by the folding of the polypeptide chains. Measurements of the phosphorescence lifetime of horse liver alcohol dehydrogenase (alcohol: NAD(+) oxidoreductase, EC 1.1.1.1) as a function of oxygen concentration indicate that internal tryptophan residues are periodically exposed to oxygen. This permits the calculation of rate constants for conformational oscillations in the enzyme. The present article illustrates the feasibility of employing phosphorescence in the study of proteins in solution in general and the utility of such experiments in probing the dynamic aspects of protein structure.
虽然溶液中芳香发色团的磷光通常会通过溶解氧的扩散和其他溶剂介导的过程而猝灭，但在室温下仍可观察到某些蛋白质在溶液中的磷光。色氨酸磷光来自那些由于多肽链折叠而受阻与氧相互作用的残基。对马肝醇脱氢酶（醇：NAD(+)氧化还原酶，EC 1.1.1.1）磷光寿命随氧浓度变化的测量表明，内部色氨酸残基会周期性地暴露于氧中。这使得能够计算该酶构象振荡的速率常数。本文阐述了一般情况下利用磷光研究溶液中蛋白质的可行性，以及此类实验在探究蛋白质结构动态方面的实用性。
