Gratton E, Jameson D M, Weber G, Alpert B
Biophys J. 1984 Apr;45(4):789-94. doi: 10.1016/S0006-3495(84)84223-X.
A model is presented for the quenching of a fluorophore in a protein interior. At low quencher concentration the quenching process is determined by the acquisition rate of quencher by the protein, the migration rate of quencher in the protein interior, and the exit rate of quencher from the protein. In cases where the fluorescence emission observed in the absence of quencher could be described by a single exponential decay, the presence of quencher led to doubly exponential decay times, and the aforementioned exit rates of the quencher could be determined from experimental data. At high quencher concentration, the processes became more complex, and the deterministic rate equations used at low quencher concentration had to be modified to take into account the Poisson distribution of quencher molecules throughout the protein ensemble and also by using a migration rate for quencher in the protein interior that is a function of the quencher concentration. Simulations performed for typical fluorescent probes in proteins showed good agreement with experiments.
提出了一种蛋白质内部荧光团猝灭的模型。在猝灭剂浓度较低时，猝灭过程由蛋白质对猝灭剂的捕获速率、猝灭剂在蛋白质内部的迁移速率以及猝灭剂从蛋白质中的逸出速率决定。在无猝灭剂时观察到的荧光发射可用单指数衰减描述的情况下，猝灭剂的存在导致双指数衰减时间，且上述猝灭剂的逸出速率可从实验数据中确定。在高猝灭剂浓度下，过程变得更加复杂，低猝灭剂浓度时使用的确定性速率方程必须进行修正，以考虑整个蛋白质集合中猝灭剂分子的泊松分布，并且还要使用蛋白质内部与猝灭剂浓度相关的猝灭剂迁移速率。对蛋白质中典型荧光探针进行的模拟与实验结果吻合良好。
