Conformation of peptides in lipid membranes studied by x-ray grazing incidence scattering.

ABSTRACT: Although the antimicrobial, fungal peptide alamethicin has been extensively studied, the conformation of the peptide and the interaction with lipid bilayers as well as the mechanism of channel gating are still not completely clear. As opposed to studies of the crystalline state, the polypeptide structures in the environment of fluid bilayers are difficult to probe. We have investigated the conformation of alamethicin in highly aligned stacks of model lipid membranes by synchrotron-based x-ray scattering. The (wide-angle) scattering distribution has been measured by reciprocal space mappings. A pronounced scattering signal is observed in samples of high molar peptide/lipid ratio which is distinctly different from the scattering distribution of an ideal helix in the transmembrane state. Beyo

SUBMITTER: Spaar A 

PROVIDER: S-EPMC1304361 | biostudies-literature | 2004 Jul

REPOSITORIES: biostudies-literature