On the color-tuning mechanism of Human-Blue visual pigment: SAC-CI and QM/MM study

Color-tuning mechanism of Human-Blue pigment, visual color-receptor in the cone cells of the eye, has been investigated. Based on the SAC-CI theoretical absorption energies, a decomposition analysis was performed and compared with the case of Bovine rhodopsin. The electrostatic effect from the opsin is primary important for the color-tuning.