New insights into the docking mechanism of vanillin on three mammalian olfactory receptors via a new statistical physics model.

A new finite multi-layer model coupled with real gas law is successfully established using statistical physics theory and applied to theoretically characterize the docking process of vanillin key food odorant on human hOR8H1, chimpanzee cOR8H1, and horse hoOR8H1 olfactory receptors. To deeply comprehend and analyze the mechanism of adsorption involved in the sense of smell, stereographic, van der Waals, and energetic metrics are interpreted. Indeed, modeling findings reveal that the vanillin molecules are non-parallelly docked on the binding sites of the three mammalian olfactory receptors. The van der Waals parameters serve as valuable tools for assessing the stability of the formed complexes during adsorption. The molar adsorption energy values, ranging from 18.26 to 20.75 kJ/mol, suggest that the vanillin molecules are exothermically-physisorbed on hOR8H1, cOR8H1, and hoOR8H1. In addition, the energetic parameter may also be deployed to quantitatively characterize the interactions between the vanillin molecules and the three mammalian receptors.