COLL 310 |
| Josef F. Holzwarth1, Henny Kell2, Sabine Couderc-Azouani2, Joachim Vater3, Undine Dietrich4, Richard Heenan5, Thomas Gutberlet6, Jeffrey Penfold7, and Christoph Boettcher8. (1) Physical Chemistry, Fritz-Haber-Institut, MPG, Faradayweg 4-6, D-14195 Berlin, Germany, (2) Physical Chemistry, Fritz-Haber-Institute, MPG, Faradayweg 4-6, D-14195 Berlin, Germany, (3) Max-Volmer-Institut, Technische Universitaet Berlin, Franklinstr. 29, Berlin, 10587, Germany, (4) Institute of Experimental Physics I, University of Leipzig, Linnestr. 5, Leipzig, 04103, Germany, (5) ISIS Facility, Rutherford Appleton Laboratories, Chilton, Didcot, Oxfordshire, OX11 0QX, United Kingdom, (6) LNS, Paul Scherrer Institut, WHGA 142, Villigen, 5232, Switzerland, (7) ISIS facility, Rutherford Appleton Laboratory, UK, Chilton, OX11 0QX, Didcot, United Kingdom, (8) FB Biologie, Chemie, Pharmazie, Frei Universitaet Berlin, Fabeckstr. 36a, Berlin, 14195, Germany |
| The bio-surfactant Surfactin possesses antifungal, antiviral and antitumural properties. We investigated the interaction of Surfactin with lipid monolayers and vesicles applying differential scanning calorimetry (DSC), static light scattering, cryo-transmission electron microscopy (TEM) fluorescence microscopy and small angle neutron scattering (SANS). Our target was to clarify how lipid membranes are influenced by the insertion of different amounts of Surfactin; this should lead to a better understanding of the biological function of Surfactin. Low concentrations of Surfactin were solubilized in monolayers or vesicles of L- a- Dimyristoyl-phosphatidylcholine (DMPC) or L- a -Dipalmitoyl-phosphatidylcholine (DPPC) and normal phase transition behavior was observed. In the range from 4-20 % of Surfactin to lipid increasing hysteresis was characteristic for the phase behavior. At higher concentrations of Surfactin the vesicles disintegrated into mixed micelles. In addition to the thermodynamic and structural investigations we also performed temperature-jump experiments to learn about the dynamics of the lipid-Surfactin system. |
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Symposium in Memory of Arthur W. Adamson
8:30 AM-11:10 AM, Tuesday, March 30, 2004 Marriott -- Orange County 4, Oral
Division of Colloid and Surface Chemistry |