title: Conformational diversity of bradykinin in aqueous solution.
abstract: The 600-MHz proton nuclear magnetic resonance spectra of bradykinin, [2-dehydroproline]bradykinin, [7-dehydroproline]bradykinin, and [5-tyrosine]bradykinin in aqueous solution have been recorded and completely assigned by means of pH variation, spin-spin decoupling, and chemical shift correlations. Analysis of the spin-spin coupling constants in the main chain and in the side chains suggests that bradykinin is in rapid equilibrium among many conformers and does not show any persistent structural features such as beta turns or internal hydrogen bonds. Addition of lipids or lipid-like materials [such as sodium (trimethylsilyl)propionate] in high concentration causes changes in the spectra, indicating specific interactions with proline-7 and phenylalanine-8, as well as a change in side-chain rotameric preference.
mesh_terms: D001920:Bradykinin; D009682:Magnetic Resonance Spectroscopy; D008433:Mathematics; D011487:Protein Conformation
chemical_list: D001920:Bradykinin