Fig. 7
From: The design of high affinity human PD-1 mutants by using molecular dynamics simulations (MD)
Distances of residues to their interacted pairs in hPD-1/PD-L1 complex during the MD simulation (a-i). The residues were the main contributors to the binding energy. The distance was increasing during the MD simulation indicated the interaction of the pair was unstable and weak, and vice versa. The interaction of K135-D61 was becoming stronger because the distance of the pair was decreasing during the simulation