Physical Chemistry, Poster
Mechanism of the cooperativity in antimicrobial peptides
E.B. Drab1, K. Sugihara1
1Department of Physical Chemistry, Univeristy of Geneva, Geneva, Switzerland
In this study we aim to elucidate the fundamental mode of action of antimicrobial cooperativity. To investigate the cooperativity between two different human peptides defensin and cathelicidin we synthesized artificial lipid bilayer onto highly doped p-type silicon electrode covered by naturally formed silicon dioxide as a clean platform to separate peptide-peptide and peptides-bilayer interactions from influence of other components within cell. Lipid bilayer was obtained by fusion of unilamellar vesicles from buffer solution and investigated mainly by impedance spectroscopy which is non-destructive and sensitive technique. In addition we performed Fluorescence Recovery After Photobleaching measurements as a complementary technique to confirm the bilayer formation by its recovery in photobleached region.

Next step in our investigation is to inject peptides and elucidate how they influence on the lipid bilayer and moreover what is the mechanism of cooperativity of two different peptides. The change in the resistance and the capacitancence will be studied at different peptide concentrations.
[1] Oliver Purrucker, Heiko Hillebrandt, Electrochimica Acta 2001, 791-798