Insight into analysis of interactions of GW9508 to wild-type and H86F and H137F GPR40: a combined QM/MM study and pharmacophore modeling

Abstract

GPR40 is a novel potential target for the treatment of type 2 diabetes. In this work, a two-layered ONIOM based QM/MM approach was employed to study the interactions between GW9508 and GPR40: wild-type, H86F, and H137F mutated systems. The calculated results clearly indicated that His137 is directly involved in ligand recognition through the NH-π interaction with the GW9508. In contrast, His86 is not interacting with the GW9508 in the NH-π interaction. The interaction energies, calculated at the MP2/6-31(d, p) level, were performed to gain more insight into the energetic differences of the wild-type and two mutated systems at the atomistic level. In addition, the obtained pharmacophore model was well consistent with structure-functional requirements for the binding of GPR40 agonists and with per-residue energy decomposition of the ONIOM calculations.