Fig. 2: Details of the distorted retinal conformation.

a S-shaped polyene backbone of retinal viewed from an upper part of Fig. 1b. The maps are shown in the same manner as in Fig. 1b. b Torsion angles along the retinal polyene chain in the K structure (7XJC) are plotted in magenta. The standard deviations, which were calculated from three structures, are indicated as error bars on the mean values shown as hollow circles. The values for respective structures are shown as crosses. The values can be found in Supplementary Table 4. Those for the ground state structure in this work (7XJD) and a recent L structure¹⁶ are plotted in gray and black, respectively. The black horizontal lines indicate angles with local minimum energies for the respective torsions.