title: Structure refinement using time-averaged J-coupling constant restraints.
abstract: We describe a new penalty function for use in restrained molecular dynamics simulations which allows experimental J-coupling information to be enforced as a time-averaged, rather than instantaneous, quantity. The pseudo-energy term has been formulated in terms of a calculated J value (a measured quantity) rather than the relevant dihedral angle (a derived quantity). This accounts for the distinct non-linearity of the coupling constant with respect to either Cartesian coordinates or dihedral angles. Example simulations of the cyclic decapeptide antamanide show the procedure's ability to enforce experimental restraints while exploring a large region of conformational space and producing a relatively small disturbance of the physical force field.
authors.affiliation: Physical Chemistry (Computational Chemistry), ETH Zentrum, Zürich, Switzerland.
authors.forename: A E
authors.initials: AE
authors.lastname: Torda
authors.forename: R M
authors.initials: RM
authors.lastname: Brunne
authors.forename: T
authors.initials: T
authors.lastname: Huber
authors.forename: H
authors.initials: H
authors.lastname: Kessler
authors.forename: W F
authors.initials: WF
authors.lastname: van Gunsteren
mesh_terms: D000595:Amino Acid Sequence; D002151:Calorimetry; D003198:Computer Simulation; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008433:Mathematics; D008962:Models, Theoretical; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000737:chemistry*; D010456:Peptides, Cyclic / Q000737:chemistry*; D011487:Protein Conformation
chemical_list: D009842:Oligopeptides; D010456:Peptides, Cyclic; C100265:antamanide