Computational simulations reveal the binding dynamics between human ACE2 and the receptor binding domain of SARS-CoV-2 spike protein

Cecylia S. Lupala; Xuanxuan Li; Jian Lei; Hong Chen; Jianxun Qi; Haiguang Liu; Xiao-dong Su

They found the association rate constants k on to be the same at 1. The copyright holder for this preprint (which was not peer-reviewed) is the . https://doi.org/10.1101/2020.03.24.005561 doi: bioRxiv preprint K353H mutants (green diamonds), the number of contacts were both reduced compared to the wild type system. In one simulation, the contacts between the CoV2-RBD and the Helix-13 of the ACE2 were completely lost (see Figure 7c) , consistent with the less favorable interactions reflected on an increase of E MM . For the SARS-RBD interaction with the ACE2-mut_h1, both simulations revealed fewer contacts compared to the wild type SARS-RBD/ACE2 complex (purple stars in Figure 8 ). Although direct observation of dissociation is beyond the reach of all-atom MD simulations, the reduced contacts for mutant ACE2 indicates the weaker binding affinity compared to the wild type human ACE2.