Observation of the cascaded atomic-to-global length scales driving protein motion.

Model studies of the ligand photodissociation process of carboxymyoglobin have been conducted by using amplified few-cycle laser pulses short enough in duration (<10 fs) to capture the phase of the induced nuclear motions. The reaction-driven modes are observed directly in real time and depict the pathway by which energy liberated in the localized reaction site is efficiently channeled to functionally relevant mesoscale motions of the protein.