Fig. 5.

Configurations based on average interatomic distances obtained by correcting distances between average positions in two locations of the KcsA ion channel (PDB ID: 1J95).²⁸ The corrections on the left-hand side of the figure are calculated for the carbonyl group (carbon atom, light blue; oxygen atom, red) of Thr75 and Val76 (in the selectivity filter) and the potassium ion K203 (green), and they represent one possible structure of the particular part of the filter assuming different types of motion: (a) correlated, (b) noncorrelated, and (c) anticorrelated. On the right-hand side of the figure, the corrections are calculated for the N^ε atoms (dark blue) of Gln119 located at the end of the channel's cavity (the gate), also assuming various types of motion. The radii of gray circles are averages of distances between the opposite N^ε atoms. All the structures in the figure have been prepared by VMD version 1.8.6.²⁹