Osella Silvio, Granucci Giovanni, Persico Maurizio, Knippenberg Stefan
Chemical and Biological Systems Simulation Lab, Centre of New Technologies, University of Warsaw, Banacha 2C, 02-097 Warsaw, Poland.
Materials and Process Simulation Center (MSC), California Institute of Technology, MC 139-74, Pasadena, CA, 91125, USA.
J Mater Chem B. 2023 Mar 15;11(11):2518-2529. doi: 10.1039/d2tb02767d.
The photoisomerization of chromophores embedded in biological environments is of high importance for biomedical applications, but it is still challenging to define the photoisomerization mechanism both experimentally and computationally. We present here a computational study of the azobenzene molecule embedded in a DPPC lipid membrane, and assess the photoisomerization mechanism by means of the quantum mechanics/molecular mechanics surface hopping (QM/MM-SH) method. We observe that while the -to- isomerization is a slow process governed by a torsional mechanism due to the strong interaction with the environment, the -to- mechanism is completed in sub-ps time scale and is governed by a pedal-like mechanism in which both weaker interactions with the environment and a different geometry of the potential energy surface play a key role.
嵌入生物环境中的发色团的光异构化在生物医学应用中具有高度重要性，但在实验和计算上定义光异构化机制仍然具有挑战性。我们在此展示了对嵌入DPPC脂质膜中的偶氮苯分子的计算研究，并通过量子力学/分子力学表面跳跃（QM/MM-SH）方法评估光异构化机制。我们观察到，虽然由于与环境的强相互作用，顺-反异构化是一个由扭转机制控制的缓慢过程，但反-顺机制在亚皮秒时间尺度内完成，并且由一种类似踏板的机制控制，其中与环境的较弱相互作用和势能面的不同几何形状都起着关键作用。
