Controlling the activity of proteins with azobenzene photoswitches is a potent tool for manipulating their biological function. With the help of light, it is possible to change binding affinities, control allostery or manipulate complex biological processes, for example. Additionally, owing to their intrinsically fast photoisomerization, azobenzene photoswitches can serve as triggers that initiate out-of-equilibrium processes. Such switching of the activity initiates a cascade of conformational events that can be accessed with time-resolved methods. In this Review, we show how the potency of azobenzene photoswitching can be combined with transient spectroscopic techniques to disclose the order of events and experimentally observe biomolecular interactions in real time. This strategy will further our understanding of how a protein can accommodate, adapt and readjust its structure to answer an incoming signal, revealing more of the dynamical character of proteins.

用偶氮苯光开关控制蛋白质的活性是操纵其生物学功能的有力工具。例如，在光的帮助下，可以改变结合亲和力、控制变构或操纵复杂的生物过程。此外，由于其固有的快速光致异构化，偶氮苯光开关可以作为引发非平衡过程的触发器。这种活动的切换启动了一系列构象事件，可以使用时间分辨方法访问这些事件。在这篇综述中，我们展示了偶氮苯光开关的效力如何与瞬态光谱技术相结合，以揭示事件的顺序并通过实验实时观察生物分子相互作用。这一策略将加深我们对蛋白质如何适应的理解，