Computational Modeling Reveals the Mechanism of Fluorescent State Recovery in the Reversibly Photoswitchable Protein Dreiklang
Computational Modeling Reveals the Mechanism of Fluorescent State Recovery in the Reversibly Photoswitchable Protein Dreiklang
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DOI：
10.1021/acs.jpcb.9b06988
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发表时间：
2019-10-24
影响因子：
3.3
通讯作者：
Nemukhin, Alexander, V
中科院分区：
文献类型：
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作者：
Grigorenko, Bella L.;Polyakov, Igor, V;Nemukhin, Alexander, V
光开关蛋白 Dreiklang 的独特性质归因于发色团咪唑啉酮环上的可逆水合/脱水反应。荧光状态的恢复与发色团脱水的化学反应相关，是该蛋白质光循环的重要组成部分。在这里，我们表征了 Dreiklang 的荧光 (ON) 和非荧光 (OFF) 状态，并使用计算方法模拟热恢复反应 OFF -> ON。通过使用包括量子力学/分子力学（QM/MM）技术在内的分子建模方法，我们表征了开态和关态的结构和光谱。结果与现有的实验数据一致。计算的反应曲线解释了观察到的恢复反应，并阐明了 Dreiklang 中含发色团的口袋中的化学转化机制。
The unique properties of the photoswitchable protein Dreiklang are attributed to a reversible hydration/dehydration reaction at the imidazolinone ring of the chromophore. Recovery of the fluorescent state, which is associated with a chemical reaction of the chromophore's dehydration, is an important part of the photocycle of this protein. Here we characterize the fluorescent (ON) and nonfluorescent (OFF) states of Dreiklang and simulate the thermal recovery reaction OFF -> ON using computational approaches. By using molecular modeling methods including the quantum mechanics/molecular mechanics (QM/MM) technique, we characterize the structures and spectra of the ON- and OFF-states. The results are consistent with available experimental data. The computed reaction profile explains the observed recovery reaction and clarifies the mechanism of chemical transformations in the chromophore-containing pocket in Dreiklang.