title: Stabilization of conformationally dynamic helices by covalently attached acyl chains.
abstract: Acylation of proteins is known to mediate membrane attachment and to influence subcellular sorting. Here, we report that acylation can stabilize secondary structure. Circular dichroism spectroscopy showed that N-terminal attachment of acyl chains decreases the ability of an intrinsically flexible hydrophobic model peptide to refold from an alpha-helical state to beta-sheet in response to changing solvent conditions. Acylation also stabilized the membrane-embedded alpha-helix. This increase of global helix stability did not result from decreased local conformational dynamics of the helix backbone as assessed by deuterium/hydrogen-exchange experiments. We concluded that acylation can stabilize the structure of intrinsically dynamic helices and may thus prevent misfolding.
authors: Lehrstuhl Chemie der Biopolymere, Technische Universität München, 85354 Freising, Germany.
authors: Bernhard C
authors: BC
authors: Poschner
authors: Dieter
authors: D
authors: Langosch
mesh_terms: D000215:Acylation / Q000502:physiology; D010455:Peptides / Q000737:chemistry*; D011487:Protein Conformation; D055550:Protein Stability; D017433:Protein Structure, Secondary / Q000502:physiology; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D010455:Peptides