• electronyc structure
• molecular dynamics
• orange carotenoid protein
• photochemistry
• surface hopping

Biological structures able to sense light and convert it in biological signals are widespread in Nature, however we have only begun to understand their working mechanism. The reason for this is that the molecular mechanisms happening in large biological matrices are very elusive phenomena that can only be studied with very advanced, and not broadly available, experimental techniques. Computational methods are very powerful tools that can be used in the study of those processes to formulate hypotheses, make predictions and connect
macroscopic observations to atomic level information. In this work, we propose the application of a method-agnostic multiscale strategy to tackle open problems regarding photo-responsive proteins. Our strategy combines a wide range of methodologies to deal with the different timescales involved in the processes, from light absorption to signal propagation. This paradigm is used in a pilot application to reveal
the mechanism of photoactivation of the orange carotenoid protein.