Mapping the ACE2 binding site on the SARSCoV2 spike protein S1: molecular recognition pattern.

Coronavirus SARSCoV2 enters the host cell via binding with the angiotensinconverting enzyme 2 (ACE2), and here we used computational modelling to study the molecular recognition pattern of this interaction. The fragment of the Nterminal part of the enzyme containing amino acids 19-45 was used as the lead peptide in this study. The structure of this peptide was systematically modified by successive replacement of its amino acids with alanine, serine, glycine, and phenylalanine. Then docking energies were calculated for all these mutant peptides. These docking energies were correlated with physical descriptors, proposed for the modelling of peptide-protein interactions, characterizing hydrophilicity and volumerelated properties of amino acid side chains. From these correlations the corresponding specificity factors were obtained for all amino acid positions, and thus the full description of the molecular recognition pattern of the ACE2 a1 domain by the virus S1 protein binding site was obtained. [ABSTRACT FROM AUTHOR]