NMR structure and dynamics of the agonist dynorphin peptide bound to the human kappa opioid receptor

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 112; no. 38; pp. 11852 - 11857
• Main Authors: O’Connor, Casey, White, Kate L., Doncescu, Nathalie, Didenko, Tatiana, Roth, Bryan L., Czaplicki, Georges, Stevens, Raymond C., Wüthrich, Kurt, Milon, Alain
• Format: Journal Article
• Language: English
• Published: United States National Academy of Sciences 22.09.2015; National Acad Sciences
• Subjects: Amino Acid Sequence; Biological Sciences; Dynorphins - chemistry; Dynorphins - isolation & purification; Dynorphins - metabolism; Humans; Ligands; Magnetic Resonance Spectroscopy; Molecular Dynamics Simulation; Molecular Sequence Data; Nitrogen Isotopes; NMR; Nuclear magnetic resonance; Peptide Fragments - chemistry; Peptide Fragments - isolation & purification; Peptide Fragments - metabolism; Peptides; Piperidines - chemistry; Protein Binding; Protein Structure, Secondary; Proteins; Receptors, Opioid, kappa - agonists; Receptors, Opioid, kappa - chemistry; Receptors, Opioid, kappa - metabolism; Tetrahydroisoquinolines - chemistry; Time Factors; molecular dynamics simulations; transferred NOE; ligand binding affinity; GPCR activation; 15N relaxation
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.1510117112

The structure of the dynorphin (1–13) peptide (dynorphin) bound to the human kappa opioid receptor (KOR) has been determined by liquid-state NMR spectroscopy. ¹H and15N chemical shift variations indicated that free and bound peptide is in fast exchange in solutions containing 1 mM dynorphin and 0.01 mM KOR. Radioligand binding indicated an intermediate-affinity interaction, with aK dof ∼200 nM. Transferred nuclear Overhauser enhancement spectroscopy was used to determine the structure of bound dynorphin. The N-terminal opioid signature, YGGF, was observed to be flexibly disordered, the central part of the peptide from L5 to R9 to form a helical turn, and the C-terminal segment from P10 to K13 to be flexibly disordered in this intermediate-affinity bound state. Combining molecular modeling with NMR provided an initial framework for understanding multistep activation of a G protein-coupled receptor by its cognate peptide ligand.