Interaction between sweet taste receptor and sweeteners using molecular dunamics simulation

Abstract

The human sweet taste receptor (hT1R2-hT1R3) is the heteromeric complex composed of T1R2 and hT1R3 in the class C G-protein-coupled receptors (GPCRs). Up to date, no crystal structure of hT1R2-hT1R3 is available, and thus homology modeling was applied here to model the hT1R2-hT1R3 complex using metabotropic glutamate receptor subtype 1 as the template. The hT1R2-hT1R3 can bind with low molecular weight sweeteners such as aspartame, neotame, sucralose, xylitol and sorbitol. In the present study, the hT1R2-hT1R3 modeled complex with xylitol or sorbitol bound were studied by molecular docking and molecular dynamics simulation. The intermolecular interactions between ligand and protein as well as binding free energies suggested that both xylitol and sorbitol preferred to bind with hT1R2 rather than hT1R3. These results could provide a more understanding of interaction between human sweet taste receptor and sweeteners (xylitol and sorbitol).