Fig. 2. Molecular determinants of B2R-ligand binding.
a Sequences of bradykinin and kallidin. b, c B2R-ligand interactions in the orthosteric ligand-binding pockets of the active B2R-Gq complexes with bradykinin (b, shown as violet sticks) and kallidin (c, shown as green sticks). Hydrogen bonds between B2R and agonists were labelled as dotted lines, and all residues participating in the interactions were shown as sticks. d, e Diagrams of the contacts between B2R and bradykinin (d) or kallidin (e).