title: Effect of the solvent on the conformation of a depsipeptide: NMR-derived solution structure of hormaomycin in DMSO from residual dipolar couplings in a novel DMSO-compatible alignment medium.
abstract: The macrocyclic compound hormaomycin has been investigated by NMR spectroscopy and by restrained molecular-dynamics simulations. Measurement of residual dipolar couplings induced by dissolving the depsipeptide in a polyacrylamide gel compatible with DMSO and their incorporation into the structure calculation of the title compound improved the precision of the family of structures. In DMSO the macrocyclic ring shows two beta-turns, whose positions in the sequence differ from those found in the CDCl3 solution structure and in the crystal structure obtained from hexylene glycol/H2O (50:50). The bulky side chain consisting of a 3-(2-nitrocyclopropyl)alanine and a chlorinated N-hydroxypyrrole moiety is flexible in DMSO.
authors.affiliation: Max Planck-Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany.
authors.forename: Uwe M
authors.initials: UM
authors.lastname: Reinscheid
authors.forename: Jonathan
authors.initials: J
authors.lastname: Farjon
authors.forename: Markus
authors.initials: M
authors.lastname: Radzom
authors.forename: Peter
authors.initials: P
authors.lastname: Haberz
authors.forename: Axel
authors.initials: A
authors.lastname: Zeeck
authors.forename: Martin
authors.initials: M
authors.lastname: Blackledge
authors.forename: Christian
authors.initials: C
authors.lastname: Griesinger
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism; D047630:Depsipeptides / Q000737:chemistry* / Q000378:metabolism; D004121:Dimethyl Sulfoxide / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D011487:Protein Conformation; D012997:Solvents / Q000737:chemistry*; D010456:Peptides, Cyclic
chemical_list: D001426:Bacterial Proteins; D047630:Depsipeptides; D004121:Dimethyl Sulfoxide; D012997:Solvents; C510371:hormaomycin; D010456:Peptides, Cyclic