Identifying human diamine sensors for death related putrescine and cadaverine molecules
Fig 3
Molecular interactions of PUT and CAD with human TAAR6 and TAAR8.
(A) Key features of the full agonist adrenaline (ADR, blue sticks) in the binding pocket of the ADRB2 active structure (PDB ID:4LDO; region comprising the TMs 3-5-6-7 in green ribbons). (B) Superposition of molecular docking of putrescine (PUT, yellow sticks), and (C) cadaverine (CAD, orange sticks), in the active-like TAAR6 (light-gray ribbons) and TAAR8 (light-blue ribbons) molecular models. Contact residues at a distance < 3.5 Å from ligands are shown in sticks and numbered according to Ballesteros-Weinstein numbering. Predicted (ligand–receptor) hydrogen bonds and salt bridge interactions are shown in dashed lines. The 2D chemical structure of PUT and CAD protonated at physiological pH, with estimated pKa1 and pKa2 for each amino group are indicated at the bottom of panels B and C, respectively.