FIDELIO GERARDO DANIEL
Congresos y reuniones científicas
Título:
Surface Properties of Amphiphilic Peptides
Autor/es:
FIDELIO G.D.,; CARUSO, B.,; AMBROGGIO E.E.
Lugar:
Santiago del Estero
Reunión:
Simposio; XLIV Reunión Anual SAB 2015.; 2015
Institución organizadora:
Sociedad Argentina de Biofisica
Resumen:

Langmuir monolayers at the air/water interface ispractically the unique technique allowing the study of the surface propertiesof peptides and proteins and their interaction with lipids in a confined ?crowded?condition similar to the that found in natural biomembranes. The surfacecompactness and surface covered proportion of the peptide compared with thelipid are quite controlled. Langmuir monolayers allow us to study the abilityof amphiphilic peptides (APs) to absorb to clean air/water interfaces, to interactwith organized lipid monolayers (penetration), lateral surface stability,AP/lipid lateral miscibility, surface rheology, conformation and secondarystructure and lateral topography.

           APs are diverse insequence and in amphiphilicity but some generalities can be achieved regardingto their surface behavior at water/air interface. Representative pure APmonolayers have similar properties than lipids when their surfacecharacteristics are compared (lateral stability and surface potential). APsacquire similar surface properties independently they absorbed from bulkaqueous phase or by spreading; a higher lateral stability observed forhydrophobic APs correlates with a higher tendency to adopt a β-sheetconformation.  In turn, this higher stability confers a greater tendencyto remain miscible in mixed lipid-peptide systems; although a higher liquidcharacter of the lipid confers a more adequate lateral environment forbidimensional miscibility.  The inversion in the sequence of peptides withthe same hydrophobicity has a particular effect on the lateral stability ofpeptide monolayers. Amyloidogenic peptides behave a higher tendency to adopt β-sheetconformation with remarkable shear elasticity.