6533b826fe1ef96bd128471a
RESEARCH PRODUCT
Size-exclusion high-performance liquid chromatography in the study of the autoassociating antibiotic gramicidin A in micellar milieu.
Concepción AbadM.c. BañóDavid Salomsubject
Circular dichroismStereochemistryProtein ConformationSize-exclusion chromatographyBiophysicsPeptideBiochemistryMicellechemistry.chemical_compoundMembrane LipidsSurface-Active AgentsProtein structureBiomimetic MaterialsColloidsChromatography High Pressure LiquidMicelleschemistry.chemical_classificationCircular DichroismGramicidinBiological membraneMembranes ArtificialCombinatorial chemistryAnti-Bacterial AgentsMembraneMonomerchemistryChromatography GelDimerizationdescription
Gramicidin A (gA) is a polypeptide antibiotic which forms dimeric channels specific for monovalent cations in biological membranes. It is a polymorphic molecule that adopts several different conformations, double-stranded (ds) helical dimers (pore conformation) and single-stranded beta-helical dimers (channel conformation). This study investigated the conformational adaptability of gramicidin A when incorporated into micelles as membrane-mimetic model system. Taking advantage of our reported, versatile, size-exclusion high-performance liquid chromatography (SE-HPLC) strategy that allows the separation of double-stranded dimers and monomers, we have quantitatively characterized the conformational transition undergone by the peptide in the micellar milieu. The importance of both hydrophobic/hydrophilic moieties of the amphipaths in the stabilization of concrete conformational species is demonstrated using detergents with different hydrocarbon chain length and/or polar head. SE-HPLC is a valuable, rapid, accurate technique for the structural characterization of hydrophobic autoassociating peptides that work in lipid environments such as biological membranes.
year | journal | country | edition | language |
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2003-06-01 | Journal of biochemical and biophysical methods |