Title:  Allosteric Dynamics in Signal Perception by Photoreceptors
Abstract:  Photoreceptors are proteins that transmit photochemical signals into chemical actions. The processes are generally characterized by ultrafast photoreceptions accompanying photochemical reactions, followed by slower processes involving protein conformational changes. The activated signals will finally return to their resting dark states. I will discuss examples on the ultrafast regulation of an excited-state energy transfer regulation by the major light-harvesting complex of photosystem II (LHCII) in response to the rapid fluctuations of light intensity, and the allosteric conformational change in cryptochrome in the activation from its autoinhibited state. In addition, I will discuss a multistate density functional theory designed to model photochemical and charge transfer processes.