Fig. 5.

(A) Cumulative stacked line graphic depicting the relative frequency of ACE2 residue contacts for each of the 15 ARBs docked into the Zn²⁺ pocket of the ACE2 receptor. Dominant amino acid contacts with ARBs included Asp, Glu, His, Leu, Phe, Ser, and Trp. Residues with the least contacts included Cys, Gln, Ile, Lys, Pro, Val. Bisartans A, B, and D were the only ARBs contacting the Zn²⁺ cofactor. (B) 2D interaction ligand-receptor diagrams of BisA, B, C, and D in the Zn²⁺ pocket of the ACE2 receptor (6LZG). Colour key for chemical interactions: green shading = hydrophobic regions; Blue shading = hydrogen bond acceptor; White dashed arrows = hydrogen bonds; Grey parabolas = accessible surface for large areas; Grey residues = “generic” van der Waals contact (non-hydrophobic, non-H-bond); Broken thick line around ligand = accessible surface; Size of residue ellipse = strength of the contact; 2D distance between residue label and ligand = proximity.