Molecular modeling studies to predict the possible binding modes of endomorphin analogs in mu opioid receptor.

The molecular docking of a series of endomorphin analog with the mu opioid receptor was performed. The successive molecular dynamics of several proposed ligand-receptor complexes inserted into the phospholipid bilayer were carried out to optimize the complex and explore the conformational changes. Meaningful differences of their binding modes were detected and the involvement of some essential residues in ligand binding was also identified. Our proposed ligand-receptor model is in good agreement with previous site-directed mutagenesis experiments.